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SERVICE TRAINING CENTER

SERVICE MANUAL
CONVEYOR RACK TYPE DISHWASHER

CNA
PRESSURE BOOSTER SYSTEM / EPROM rev. 3.00
This document is destined for internal use only. The discribed settings and servicing must be carried out by service technicians qualified by HOBART. Reproduction of this document is prohibited without the written permission of Hobart GmbH. © HOBART GmbH, Service Training Center
Issue: 2005-04

Important Note
For filling and first run the technician need this manuals, and he must follow the instructions to prevent damage of the booster heating elements

SERVICE TRAINING CENTER

CONTENTS
CNA MODULES ................................................................................................................................... 3 TECHNICAL DATA ............................................................................................................................... 4 MACHINE DOCUMENTS ..................................................................................................................... 4 CONTROLS .......................................................................................................................................... 5 INITIAL OPERATION ........................................................................................................................... 6 WATER CIRCULATION AND HEAT BALANCE .................................................................................. 7 FUNCTIONAL DESCRIPTION ............................................................................................................. 8 OPERATION .................................................................................................................................... 8 TANK FILL ....................................................................................................................................... 8 BOOSTER ....................................................................................................................................... 8 WASH OPERATION ........................................................................................................................ 8 AUTOTIMER .................................................................................................................................... 9 DRAINING ..................................................................................................................................... 10 SAFETY CIRCUIT ......................................................................................................................... 11 DOOR SWITCH ............................................................................................................................. 11 FLOAT SWITCHES ........................................................................................................................ 11 TEMPERATURE SENSORS .......................................................................................................... 11 WASH SYSTEM ................................................................................................................................. WASH PUMPS .............................................................................................................................. WASH ARMS ................................................................................................................................. LATERAL WASH (OPTION) ........................................................................................................... E-PREWASH ................................................................................................................................. 12 12 13 14 14

RINSE SYSTEM ................................................................................................................................. 15 FINAL RINSE ................................................................................................................................. 15 PRE-RINSE SYSTEM ......................................................................................................................... 16 DUAL RINSE .................................................................................................................................. 16 TRIPLE RINSE .............................................................................................................................. 17 RINSE PUMPS ................................................................................................................................... 18 TANK AND BOOSTER HEATING ...................................................................................................... 18 ELECTRICAL HEATING ................................................................................................................ 18 HEAT RECOVERY .............................................................................................................................. 19 DISPENSERS ..................................................................................................................................... 19 CONTROL PANEL ............................................................................................................................. 19 CONVEYOR SYSTEM ........................................................................................................................ MACHINE CAPACITY .................................................................................................................... TABLE END SWITCH .................................................................................................................... CONVEYOR SAFETY MECHANISM ............................................................................................. TRANSPORT SYSTEM ................................................................................................................. REPLACEMENT OF GEAR MOTOR ............................................................................................. 20 20 20 20 20 20

POSITION OF CURTAINS .................................................................................................................. 21 FAULT DISPLAY ................................................................................................................................. 22 STARTING FROM EPROM REVISION 3.00 .................................................................................. 22 UP TO EPROM REVISION 2.00 (FOR INFO) .............................................................................. 23

Page 2 ­ CNA Series (rev. 3.00)

© HOBART GmbH, Service Training Center

SERVICE TRAINING CENTER

CNA MODULES
CNA
1.950

CNA-E
2.150

1.718 1.576

CNA-L
2.600

1.718 1.576

CNA-S
2.850

1.718 1.576

1.718 1.576

790 300

CNA-C
391

500

1.025 1.325

303

1.025 2.375 2.675

1.350 300

850

300

1.718

430

2.208

900

2.013

© HOBART GmbH, Service Training Center

2.013

CDS

CDC

CNA Series (rev. 3.00) ­ Page 3

SERVICE TRAINING CENTER

TECHNICAL DATA
MODEL Capacity (racks - plates / hour) standard accordant DIN0510 Prewash Pump load (kW) Delivery rate (l/min) Tank volume (l) Wash Pump load (kW) Delivery rate (l/min) Tank volume (l) Rinse Water consumption (l / hour) Dryer Heating (kW) Air circulation (m-/h) Fan motor (kW) Equipment 2 speeds Auto-timer Isolating switch Dual rinse Triple rinse Heat recovery C30 Heat pump CHP18 yes Option Option yes Option Option Option yes Option Option yes Option Option Option yes Option Option yes Option Option Option yes Option Option yes Option Option Option yes Option Option yes Option Option Option 4.5 / 9 1800 0.42 4.5 / 9 1800 0.42 4.5 / 9 1800 0.42 4.5 / 9 1800 0.42 4.5 / 9 1800 0.42 260 260 260 260 260 1.5 1020 100 1.5 1020 100 1.5 1020 100 1.5 1020 100 1.5 1020 100 ­ ­ ­ 0.3 250 30 1.1 740 54 1.5 1020 100 1.1 740 54 120 - 2160 80 150 - 2700 100 180 - 3240 120 220 - 3960 150 180 - 3240 120 CNA CNA-E CNA-L CNA-S CNA-C

MACHINE DOCUMENTS
Wiring diagrams and general machine data are stored in a pocket at the rear of the hinged electric box.

Page 4 ­ CNA Series (rev. 3.00)

© HOBART GmbH, Service Training Center

SERVICE TRAINING CENTER

CONTROLS

6
1. Machine ON / OFF

1

4

3

2

5

Emergency Stop (option)

Pushing this button switches the dishwasher on or off. NOTE: After switch off, the machine is not voltage free! At the temperature indicator Rinse appears a point.

2. Start / Stop button ­ Conveyor / Wash Pushing this button starts the conveyor with the selected speed. The button illuminates to indicate the mode of the machine: RED = machine fills and starts heating GREEN = machine is ready for operation BLUE = washing on

When the button flashes: RED = when switching on the machine: machine is filled but heating-up fault: the temperature indicators display a code GREEN = machine refills and heats up BLUE = program started, but machine is not ready for operation
3. Conveyor speed button By pushing this button, it is possible to select between two pre-set conveyor speeds. The selected speed will be indicated. By pushing this button for approx. 4 seconds, temperatures will be indicated. "Ch0" = rinse / "Ch1" = wash "Ch2" = prewash (option ­ activated by S03 in configuration mode) The temperatures will be displayed one after the other by repeated pushing the Conveyor speed button. The indicators go out 10 seconds after releasing the button. 4. Conveyor speed indicator Indicates the selected speed. = slow = fast When the conveyor speed indicator flashes, the table end switch is activated [1S6]. 5. Temperature indicators Indicates the current temperature: Temperature indicator Rinse (°C) Temperature indicator Wash (°C)

With a machine malfunction, the temperature indicators display a code.
6. Drain button By pushing this button for approx. 2 seconds, only the prewash tank will be drained. The drain button illuminates and the Start / Stop button illuminates red. After a pre-set time (C04) drain cycle stops and the machine will be refilled automatically. To drain the machine completely, push drain button for approx. 4 seconds. The drain valves will be controlled via adjustable time delay [C05]. The Drain button illuminates and the Start / Stop button switches off.
© HOBART GmbH, Service Training Center CNA Series (rev. 3.00) ­ Page 5

SERVICE TRAINING CENTER

INITIAL OPERATION
FILLING THE RINSE BOOSTER FOR THE FIRST TIME This is necessary after setting the machine type, when the dishwasher has been initially installed or when the booster has been drained (to prevent frost damage or to replace heating elements for instance). ­ Remove lower front panel and switch on all circuit breakers and motor protection switches in the control box. ­ Open shut-off valves at site and switch on main switch. When switching on the machine, the temperature indicator displays flashing: This indicates that the booster is empty and requires filling. For the initial fill of pressure booster, the rinse pump has to be energised. This can be carried out via the test mode after the break tank is filled (via mechanically operated float valve): Switch off the machine by pushing the ON/OFF button and open the doors. Push and hold the drain, conveyor speed and Start / Stop button together. The temperature indicators display: S01 corresponds to the first tested input (doors) of the control board.

Close the doors. The wash temperature display changes to --1. Generally the switch settings are displayd with --1 when activated (close) and --0 when inactive (open). Push the Conveyor speed button repeatedly until the temperature indicator rinse displays "A17" (output rinse pump). Push the start button (--1 appears in the wash temperature display) and hold until water sprays out of rinse nozzles. Switch off main switch. Remove electr. control cover and put the provided jumper on X2 (16/17). Put the control cover and front panel in place. Switch on main switch but not the machine.

Open doors, push the drain and conveyor speed button together.

The temperature indicators display:

To clear the message, push the start button

.

The temperature indicators display:

The wash temperature display will change immediately to --0. Close the doors. The indicators go out and the machine is now ready for operation.

NOTE: After setting the machine type or reset of the parameter C28 to "0", BOF will also be indicated and the initial booster fill has to be repeated.

Page 6 ­ CNA Series (rev. 3.00)

© HOBART GmbH, Service Training Center

CNA-S-CDS with triple-rinse

30°C 600 m3/h

SERVICE TRAINING CENTER

© HOBART GmbH, Service Training Center

1B6
ca. 45°C
ca. 55-60°C

auto-timer

ca. 60°C ca. 70°C 900l/h ca.85°C 260l/h

1S1

1S6 2B2
rinse agent dosage ca. 0.5 g/l table end switch

1B2

1.5 g/l 3 g/l blocking

M
1S5 3Y1

1Y11

WATER CIRCULATION AND HEAT BALANCE

ca. 10°C

2Y1

> 45°C

CNA Series (rev. 3.00) ­ Page 7

1Y2

SERVICE TRAINING CENTER

FUNCTIONAL DESCRIPTION
OPERATION When the machine is switched off, a luminous red point (at the rinse temperature display) indicates that the machine is connected to the main power supply. Switching on the machine:

Note: When switching on the machine, a test program of the control (inputs and outputs) will run and the control panel is locked during this time. Therefore you should wait approx. 5 sec., before commands are given via control panel.
When the doors are closed and the machine is switched on by pushing the ON/OFF button , fill will be started.

TANK FILL Via separate fill valve (hot water connention) [S18 = 1] The machine will be filled by the cascade principle via warm water valve 1Y2. When all float switches [1B2 & 2B2] of the machine are activated, the heatings in the respective tanks will be switched on. Then the machine will be overfilled via adjustable time [C02] (see service mode). Refill during operation is controlled via timer [C03]. The conveyor start button illuminates red during the fill and heating phase and will change to green light when all operation temperatures (adjustable) are reached. Via booster: machines with 1 cold water connection [S18 = 0]: When the machine is switched on, first the booster will be heated [1K1]. If 70°C [F01] are reached, the rinse pump 1M3 will start and the tanks will be filled via the rinse pipes. Machine fill via booster can be temperature-controlled by parameter [S14 = 1]. In this case the booster will be heated up to 70°C before the rinse pump 1M3 will be started to fill the machine. If the temperature drops below 48°C, fill (rinse pump) will be stopped until the booster has reached 70°C again. Fill time control The fill time of the machine will be controlled via adjustable time [C09] (base value = 30 min). When the respective float switch has not close after this time period, the error message FIL 002 will be displayed. The fault will be cleared as soon as the float switch closes again. The filling of the machine remains activated when the failure occurs.

NOTE: The exhaust ventilator will also be controlled during the whole fill time.
BOOSTER When the machine is switched on, the pressure pump will be started for approx. 5 sec. [C17] to guarantee refilling of the pressure booster in case of water loss (e. g. evaporation or leakage during a longer standstill period). During the machine tanks are filled, the booster will be heated up to 70°C [F01]. When the tanks are filled ( after time delay [C02] ), the booster will be heated up to 85°C ( set value [F02] ). WASH OPERATION When the machine is ready for operation, the conveyor can be started by pressing the conveyor start button The conveyor speed (slow / fast) will be selected by pressing the conveyor speed button and indicated by the LED.

.

Note: The conveyor can only be started when the machine is filled (re-fill completed) and the set value of 85°C is reached in the booster.

Page 8 ­ CNA Series (rev. 3.00)

© HOBART GmbH, Service Training Center

SERVICE TRAINING CENTER

FUNCTIONAL DESCRIPTION
AUTOTIMER As a rack enters the machine, the auto timer actuator lever (magnet) triggers a reed switch [1S1] and the wash functions of the machine will be started. Each signal of the magnet activates a time delay which will stop the wash function when the last rack has passed the machine (autotimer) [C08] / [C44]. The conveyor is still working and wash will start again as soon as a rack enters the machine (lever pulse). For every speed a separate wash time via autotimer is adjusted. At speed 1 (slow) the autotimer is controlled via time [C08] and at speed 2 (fast) via [C44]. If during wash operation the table end switch [1S6] is activated by a rack, the conveyor will be stopped immediately as well as rinse and pre-rinse if activated. If the rack isn't removed, the wash pumps will stop after 45 sec. [C06]. The activated table end switch [1S6] will be indicated by the flashing conveyor speed indicator. If the end switch is free, the conveyor will start again with the chosen speed. Rinse and pre-rinse will also be started if activated by a rack. The autotimer [C08] or [C44] will be reactivated and wash will be started again. Autotimer rinse
pre-wash main wash (AR) dual and final rinse dryer

auto timer switch 1S1 (at machine entry) 01-242189-1 (L/R) 01-242189-2 (R/L)

auto-timer wash [C08] parameter at speed 1 switch-on delay rinse [C46] rinse time [C47] + rack length auto-timer wash [C44] parameter at speed 2 switch-on delay rinse = [C46] x [C50] (%) rinse time [C47] x [C50] (%) + rack length

1S1
rack entry detection transport motor 2 speeds (factor 2/3)

After wash is switched on via autotimer [1S1], pre-rinse (option) and final rinse will be activated time delayed (depending on chosen conveyor speed) for a preset time. The rinse period is also adjustable according to conveyor speed. At speed 1 (slow) rinse will be started time delayed via [C46] after the rack switch [1S1] was activated. The rinse time is given by [C47] and by the contact time (rack length) of switch [1S1]. So the rinse time is equal [C47] + contact time of [S1]. Every new rack will be registered, the respective time will be measured and executed. The rack before will keep its turn on and turn-off times. If the conveyor was stopped (e.g. by the table end switch or by the operator), the times will be stored and the autotimer functions will proceed after restart.

© HOBART GmbH, Service Training Center

CNA Series (rev. 3.00) ­ Page 9

SERVICE TRAINING CENTER

FUNCTIONAL DESCRIPTION
The functions of conveyor speed 2 (fast) are the same as described for speed 1. As the rack enters the pre-rinse (option) and final rinse zone faster than with speed 1, other times are required. This time will be proportionally calculated of parameter [C46] which corresponds to the slow speed. The conversion factor is indicated in % via [C50] and is normally set to 67%. This value corresponds to the transmission between slow and fast speed of the conveyor motor. The effective rinse time of a rack will be calculated the same way via [C47] and [C50].

NOTE: If during wash operation the machine will be refilled or a temperature drops below the preset value, the blue illuminated conveyor start button will flash until the normal operation conditions are reached again. During stand-by the conveyor start button is flashing green in this case.
Automatic conveyor switch-off After wash is switched off via autotimer, the conveyor will be stopped automatically after the adjustable time [C07 = 300 sec.]. To start again, the conveyor start button must be pressed or a rack must enter the machine. The automatic re-start via rack switch [1S1] is only possible after the mechanical conveyor has been started one-time by pushing the start button. rinse switch in the AR zone Mechanical rinse switch (option) The autotimer rinse function (controlled by the software) can be realized alternatively via an additional mechanical switch. Pre-rinse and final rinse will be started as long as the switch is activated. With this option the parameters [C46] and [C47] must be set to "0". Parameter [S01] (configuration) must remain activated resp. set to "1".

DRAINING Partial draining Pressing the drain button for approx. 2 sec. will initiate a partial draining of the machine if prewash tank is installed [S03 = 1]. The drain button illuminates and the conveyor start/stop button illuminates red . The drain valve of the prewash tank will be activated for an adjustable time [C04]. After this time period the valve will be closed and the prewash tank will be refilled. Complete draining Pressing the drain button for approx. 4 sec. will initiate a complete drain of all tanks. The drain button illuminates and the red conveyor start/stop button switches off . All drain valves will be activated for an adjustable time [C05]. After this time period the valves will be closed and the machine will be switched off (ON/OFF button is no longer illuminated). If the machine will be switched off before draining (partial or complete) has finished, only the drain button remains illuminated. To stop a drain cycle, machine must be switched OFF and ON again (ON/OFF button). Draining (partial or complete) can also be done with doors open. Drain control When drain cycle is completed resp. the drain valves close (after time period C4 & C5), the float switches of the respective tanks must be free again. If not, an error message will be displayed (see also page 22): AL1 = drain fault ­ prewash tank / AL0 = drain fault ­ wash tank.

Page 10 ­ CNA Series (rev. 3.00)

© HOBART GmbH, Service Training Center

SERVICE TRAINING CENTER

FUNCTIONAL DESCRIPTION
SAFETY CIRCUIT The security circuit controls the doors and the conveyor system (motor protection and jam switch) [1S5]. If the circuit is interrupted, wash functions will be switched off and only the heaters will be activated.

NOTE: The safety circuit does not control the release of motor protection switches (wash pump motors etc.) and therefore it will not display any fault.

DOOR SWITCH The door reed switch is located behind the front panel at the lower tank support, the magnet is fitted at the door stop. The door contacts [..S2] are wired with the safety circuit and interrupt the washing functions of the machine. The door contacts must be connected to the wiring harness with plugs which can be replaced by AMP-plugs if defective.

FLOAT SWITCHES All tanks are equipped with a float switch which will activate or switch off the heater (depending on temperature). The float switch is a change-over contact which will disable the fill contact and enable the heating at upper level [..B2] (1-2 opens, 1-3 close).

TEMPERATURE SENSORS The temperature sensors (NTC) can be checked by resistance measuring. Check also for earth fault as this can cause galvanic currents which could result in pitting corrosion. For this test (500 V DC, R > 1 M Ohm) both wires must be short-circuited to prevent damage of the sensors. The temperature sensors are attached to the exterior wall of the respective wash tanks and booster. Temperature adjustment is not possible. temperature °C 0 1 5 10 20 30 40 50 55 resistance kOhm 35.979 34.325 28.519 22.765 14.774 9.787 6.653 4.608 3.856 temperature °C 60 65 70 75 80 85 90 100 resistance kOhm 3.243 2.745 2.333 1.990 1.704 1.464 1.262 0.950

© HOBART GmbH, Service Training Center

CNA Series (rev. 3.00) ­ Page 11

SERVICE TRAINING CENTER

WASH SYSTEM
WASH PUMPS Modul prewash E prewash L prewash S prewash C wash AR pump load 0.2 kW 1.1 kW 1.5 kW 1.1 kW 1.5 kW delivery rate 250 l/min 740 l/min 1200 l/min 740 l/min 1200 l/min tank volume 30 l 54 l 100 l 54 l 100 l

Replacement of the mechanical shaft seal 1. Remove clamps (1) & (2). Take down the pump, turn over and set it down onto the motor. Be carefully that no water run into the motor. 2. Loosen the self-locking nut (3) and remove washer (4) & spacer (5). 3. Remove the impeller (6). 4. Dismantle the shaft seal (7). 5. Clean shaft and support before fitting the new shaft seal. 6. Installing the the new shaft seal 324 815-4 : a) Wet the rubber collar of the ceramic part with rinse aid. b) Press ceramic part right-angled into place. The ceramics surface must not be damaged. c) Clean the ceramics surface and wet it with paraffin oil. d) Wet the inner rubber ring oft the shaft seal with rinse aid and put some paraffin oil to the sealing face. 2 e) Press shaft seal against the ceramic ring. 7. Reinstall carefully the impeller. 8. Mount spacer (5), washer (4) and nut (3) and tighten. 9. Use new o-ring (8) 276903-27 & (9) 276903-31 for reassembling the pump.

13 14

9

1
Wash pump construction To optimise the pump capacity, a throttling ring (10) is fitted between lower part of pump housing (11) and impeller (6). Pay attention to mounting direction! When the pump housing will be replaced, a new o-ring (12) 276903-28 must be fitted.

7

6 5 8 12 4 3 10

NOTE : If the shaft seal is leaky, the o-ring (13) prevent water splashing into the motor. The water run into the upper pump housing (14). Therefore let it drain before turning the motor on top when dismounting Cr-Ni cover 695797-39 is available for machine installation.

Impeller Ø168 mm Ø152 mm Ø120 mm

Part no. 774 146-1 774 147-1 774 146-2

Pump 1.5 kW/ 50Hz 1.5 kW/ 60Hz 1.1 kW/ 50-60Hz

11

Page 12 ­ CNA Series (rev. 3.00)

© HOBART GmbH, Service Training Center

SERVICE TRAINING CENTER

WASH SYSTEM
WASH ARMS The wash arms consist of a different number of pipes with 7 nozzles per pipe: wash arm L prewash S, A wash C prewash upper 3 pipes 6 pipes 4 pipes lower 1 pipe 4 pipes 3 pipes
8 3

6 5 7

4 8

1
9 13

The illustration shows the wash system of a main wash tank. The rounded plastic manifolds (3) are mounted to the rear surface of tank and fixed with plastic nut (4) and gasket (5) from inside. This nut serves as wash arm support. The wash pipe gasket (6) will be pressed into nut (4) and fixed with the diaphragm (7). To mount the wash arm (1) set it in side guides (8), move to end position and drop-in over stop unit (9). To remove the upper wash arm press latch (see arrow), lift wash arm over stop unit and pull out. The front of the wash pipes will be sealed by pressed-in rubber plugs (13).
12 11 2

11

10

Special tool is needed for the replacement of wash arm guides resp. manifold (available as ring wrench 695797-36 or socket wrench 695797-81).

To avoid tilt over of dishes and to reduce splash over of wash water, the upper wash arms are placed in such a way, that the first two water jets do not hit a lower one.
operating direction

Diaphragm Every nut (4) is provided with a diaphragm (7 + 12) to distribute the pump pressure on upper and lower wash arms in a way, that a good washing result will be achieved with different kinds of washware and dishes do not tilt over. diaphragm Ø / part no. 14 mm / 885 538-4 24 mm / 885 538-1 12 mm / 885 538-6 "C" corner prewash upper arm lower arm "L" prewash lower arm upper arm "S" prewash + AR wash lower arm upper arm

© HOBART GmbH, Service Training Center

CNA Series (rev. 3.00) ­ Page 13

SERVICE TRAINING CENTER

WASH SYSTEM
LATERAL WASH (OPTION) The part (1) shows the wash nozzle at the back side (3 x) which is mounted to the manifold by means of a nut. An additional wash pipe (2) with three nozzles is fitted on front side. The parts (1) and (2) are different on machines with left-to-right or right-to-left operating direction. The water jet is directed against the operation direction.

1 2

3

2

3

E-PREWASH The "E" prewash system consists of a 30 l tank and two wash arms (2), supplied by a 0.2 kW pump (1) with a delivery rate of 250 l/min.
2

The wash arms (2) are equipped with a diaphragm (3) to ensure a pressure of 0.2 bar (upper) resp. 0.1 bar (lower).

1

Page 14 ­ CNA Series (rev. 3.00)

© HOBART GmbH, Service Training Center

SERVICE TRAINING CENTER

RINSE SYSTEM
The rinse zone is connected to the last wash tank (AR module) as standard. The rinse zone consist of two systems, prewash (option) and final rinse. FINAL RINSE The final rinse water is needed to remove residual detergent and to reduce the surface tension in combination with rinse aid. The temperature of 85°C enables dishes to dry and ensure the hygiene regulation. The water streams through the line strainer into the break tank (1) (airgap). The water level in the break tank is controlled by the mechanically operated float valve (2). The rinse pump (3) delivers the water through the condensers (C1 and C2) and through the booster (8) into the final rinse arms. In the condensers the water will be heated up to approx. 40 - 45°C. The booster (8) will heat the water to 85°C. The heating elements (11) are controlled by a temperature sensor (10). The safety relief valve (9) shall prevent that the pressure exceeds 2 bar in case of fault. The final rinse water consumption of 260 l/hr will be controlled by a diaphragm (4) at the rinse pump (3) outlet0. Diaphragm according to machine type:

7 C2

with heat recovery C30 699119-47 (Ø 5.3 mm) without heat recovery C30 699119-48 (Ø 4.5 mm)

The backflow preventer (7) is installed to avoid emptying of the system.

C1

Both rinse arms are equipped with 4 nozzles (interchangeable): 885 520-6

13 1 9 12 10 5 4 8 14 3
© HOBART GmbH, Service Training Center

Rinse agent connection (13) is provided above the rinse booster heater (R 1/8" inside).

Draining: Turn out plug (14) for the drain fitting of rinse booster heater (8). Disconnect hose (rinse pump) at the bottom of the break tank (1) and let it drain.

11

CNA Series (rev. 3.00) ­ Page 15

SERVICE TRAINING CENTER

PRE-RINSE SYSTEM
The CNA can be delivered with three types of rinse system: ­ mono rinse ­ dual rinse ­ triple rinse

DUAL RINSE The final rinse water passes into the dual rinse tank and will be used for pre-rinse.
2

At this system, the final rinse water will be passed into the main wash tank via the dual rinse tank. The pre-rinse system will not be installed at machines with mono rinse. Hereby the recirculating pump (1), rinse arms (2 + 3) and drain valve (4) are not fitted. When complete draining of the machine is activated, draining of the dual rinse tank will be executed via the connection to the main wash tank.

3

ns -ri no ank mo t ith wash w ­>

e

4 1

When complete draining of the machine is activated, draining of the dual rinse tank will be executed directly to drain via valve (4).

Page 16 ­ CNA Series (rev. 3.00)

© HOBART GmbH, Service Training Center

SERVICE TRAINING CENTER

PRE-RINSE SYSTEM
TRIPLE RINSE The final rinse water enters the dual rinse tank (5 l volume) and will be circulated by the dual rinse pump (1) which is not installed at machines with mono rinse system. The delivery rate of approx. 700 l/h is given by the impeller (Ø 51.5 mm) and the nozzles (4 x Ø 2.3 mm at each rinse arm (2, 3 and 4)).

At machines with triple rinse, residual detergent on dishes will be removed by pre-rinse. Approx. 160-200 l water will be passed from the upper rinse arm (2) via T-piece to an especially designed nozzle (3) with a broad spraying angle. This water removes approx. 80% of detergent and passes directly into the wash tank to prevent high detergent concentration in the dual rinse tank. The water in the dual rinse tank will also be regenerated by permanently incoming final rinse water. The remaining water (approx. 50-80 l) passes via branch connection into the prewash tank. This water flow is regulated by the built-in diaphragm (5). At machines without prewash tank, the water passes directly to drain via the diaphragm (6).

2

3

4

6 5

wi

th

w pre

as

h

without prewash <­ drain

7 1

When complete draining of the machine is activated, draining of the tank will be executed directly to drain via valve (7).

© HOBART GmbH, Service Training Center

CNA Series (rev. 3.00) ­ Page 17

SERVICE TRAINING CENTER

RINSE PUMPS
Hanning Pump: 781237-1 connector

2

Condenser Connection Diagram Pump Motor
Code no. 42617

3

pos. (2) (3) (4)

part no. 774 986-104 (51.5 mm) 276 903-43 ML 102854 (pos. (3) included)

4

Motor connection In case of overheating the pump will be switched off by the integrated thermal protection. The coil protection will reset after a cooling down period.

The pump delivery rate is given by the impeller: Pump (230/1/PE) function rinse pump (pressure booster) rinse pump (pressureless booster) dual rinse E-prewash part no. 781 237-2 781 237-1 781 237-1 781 237-2 diameter 72.0 mm 51.5 mm 51.5 mm 72 mm impeller part no. 774 986-101 774 986-104 774 986-104 774 986-101

TANK AND BOOSTER HEATING
All wash tanks and the booster are provided with an electrical heating element or a heating coil when steam or hot water heated. There are no heating elements in the prewash tanks (E, L, S or C). In these tanks the temperatures (40-50°C) will be reached by wash tank overflow and regeneration.

ELECTRICAL HEATING The tank heating elements are equipped at one connection with an internal thermal fuse (tripping temperature 167°C) and must be fitted with this side on top (see "TOP" mark). The tank heaters consist of three elements (one element per phase) and have one or two heating coils depending on loading Nominal voltage, loading (kW ­ equivalent to the nominal voltage), part number and the "TOP" mark are stamped on the flange. The specified loadings (see data plate, wiring diagram, documents etc.) are based on a supply voltage of 230V ~.

Page 18 ­ CNA Series (rev. 3.00)

© HOBART GmbH, Service Training Center

SERVICE TRAINING CENTER

HEAT RECOVERY
600 m3/h exhaust air will be sucked by the exhaust ventilator (0.11 kW) via two heat exchangers. As a result the supply rinse water will be heated to about 40-45°C, provided that the panels are closely mounted and all curtains are in place. Required exhaust volume at site is 1000 m3/h. Otherwise a vent hood with additional ventilator (available as an option from HOBART) can be used. If the hood is connected to outside, an anti-freeze shutter ("A") must be provided.

"" A
exhaust fan 600 m3 / hour

DISPENSERS
Normally, dispensers and controls are delivered and installed by the detergent and rinse agent suppliers. Please pay attention to the following rules: ­ in principle, the detergent will be dosed in the last wash tank. ­ rinse agent connection is provided above the rinse booster heater (R 1/8" inside). The dispensers have to be installed according to wiring diagram. Terminals (XD) (230V) are provided in the control box (see wiring diagram): XD/1: operation XD/4: rinse XD/2: fill XD/N: neutral wire XD/3: wash The connected load of both dispensers must not exeed 70 VA.

CONTROL PANEL
Pos. (1) (2) (3) (4) Part no. 898 363-001 897 501-001 785 446-002 895 770-001

3 2 1

4

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CNA Series (rev. 3.00) ­ Page 19

SERVICE TRAINING CENTER

CONVEYOR SYSTEM
MACHINE CAPACITY Alternatively the CNA can be operated with two conveyor speeds resp. two different capacities (racks/hour). Depending on configuration (module system) the capacity of the machine (also conveyor speed resp. transmission) vary to ensure DIN 10510 (contact time = 2 minutes). Model CNA CNA-E CNA-L CNA-S CNA-C capacity racks/h* 80/120 100/150 120/180 150/220 120/180 gear (400V-50Hz) 494 947-04 494 947-03 494 947-02 494 947-11 494 947-02

7 6

*with 50Hz / the least capacity corresponds to the contact time demanded by DIN.

4 5

8
TRANSPORT SYSTEM The gear motor (1) (fitted below the AR tank) turns a disc (2) via clutch system (11). The axle (3) (excentrically fixed to the disc (2)) moves inside the chamber (4), coupled to the support (5). This support moves the rails (6) forward / backward with a range of approx. 90 mm, given by the diameter of the disc (2). The dogs draw up in operation direction and take the rack along. In opposite direction the dogs tilt over and the rack stays on the rail. Coupling different rails will realise the transport system through the complete machine, also for machines with curves. The gasket (10) is used to seal the tank. The gear shaft will be protected against soil and water by the cap (17).

TABLE END SWITCH This switch [1S6] (at the end of the exit) will be actuated when rack is not unloaded from the conveyor. After removing the rack, the transport 17 moves on automatically.

3 2

9
CONVEYOR SAFETY MECHANISM If conveyor jams, the motor (1) (which is bolted to vertical plate) turns the vertical plate (12) on its pivot (13), thereby operating the trip switch (14) [1S5 in wiring diagram] and stopping the machine. The sensitivity of the system will be adjusted by spring (15) tension via adjusting screw (16).

10

11

1

12
REPLACEMENT OF GEAR MOTOR When replacing the gear motor pay attention to the correct rotation direction to ensure that in case of blockage the safty end switch [1S5] will trip.

13 15 16

14

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SERVICE TRAINING CENTER

POSITION OF CURTAINS
As there are different curtains, additional hooks and different rod lengths are used to prevent confusing. Illustrations are based on left-to-right operating machines. The position of curtains is mirrorwise in case of rightto-left operation.

325 360-7
655 630

325 360-6
645 660

325 360-7
655 630
292

325 360-7
655 630

429

1

419

2

3

495

4

781 067-1

781 033-1

781 284-1

781 067-2

Prewash modules

1 3

2

1 3

1 3

2 3

1 3

2 3

C

E

L

S

Wash modul

1 3

2

4

AR

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CNA Series (rev. 3.00) ­ Page 21

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FAULT DISPLAY
STARTING FROM EPROM REVISION 3.00

CODE FIL 001

FAULT DESCRIPTION Exceeded filling time ­ booster.

POSSIBLE CAUSE The booster fill is controlled via adjustable time (C10). When this time has expired and the float switch is not closed: None or not enough water at site, cold water valve defective, water consumption too high etc. This fault will only occur at machines with pressureless booster and retrofitted Eprom Rev. 3.00.

FIL 002

Exceeded filling time ­ tank.

The wash tank water level is controlled via adjustable time (C09). When this time has expired and the float switches are not closed: None or not enough warm water at site, fill valve defective, strainer, drain valve leaky, float switch defective, splash-over. When the drain time C05 has expired, the float switches must be open. If not: Drain valve defective, drain system clogged, float switch defective etc. The corresponding heaters are locked until the fault is eleminated. To clear the fault message: switch off machine via main switch.

AL0

Drain fault ­ wash tank.

AL1

Drain fault ­ prewash tank.

Once the drain time C04 has expired, the float switch must be open. If not: Drain valve defective, drain system clogged, float switch defective etc. To clear the fault message: switch off machine via ON/OFF button.

AL2

Doors fault.

Security circuit X8 / 1-2 open: Doors open, reed switches, safety end switch transport actuated (1K8) Input X9 / 1-3 closed: Check detergent and rinse agent container. The connection (RS232) of the two PCBs is broken. Communication fault between the two PCBs There are two possible messages: - - 1 = short circuit / - - 2 = open circuit General temperature fault. General temperature fault. General temperature fault.

AL3 -E001 -CF01 F02 F03 F06

Deterget or rinse agent deficiency (option). Bus system failure Master slave fault Temperature probe "booster" defective. Temperature probe "tank" defective. Temperature probe "prewash tank" defective. Temperature probe "fill booster" defective.

HEATPUMP (Option) AL5 001 Low pressure The compressor has been switched off 4 times within an adjustable time by pressure switch 1B5 (LP). Switching cycle and time control are stored in parameter C24 (= 4) and C42 (= 900 sec). The compressor has been switched off 4 times within an adjustable time by pressure switch 1B5 (HP). Switching cycle and time control are stored in parameter C25 (= 4) and C42 (= 900 sec). Switch on motor protection switch. switch off machine via ON/OFF button

AL5 002

High pressure

AL5 003

Motor protector compressor tripped To clear the fault messages:

Page 22 ­ CNA Series (rev. 3.00)

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FAULT DISPLAY
UP TO EPROM REVISION 2.00 (FOR INFO)

CODE FIL 001

FAULT DESCRIPTION Exceeded filling time ­ booster.

POSSIBLE CAUSE The booster fill is controlled via adjustable time (C10). When this time has expired and the float switch is not closed: None or not enough water at site, cold water valve defective, water consumption too high etc. The wash tank water level is controlled via adjustable time (C09). When this time has expired and the float switches are not closed: None or not enough warm water at site, fill valve defective, strainer, drain valve leaky, float switch defective, splash-over. When the drain time C05 has expired, the float switches must be open. If not: Drain valve defective, drain system clogged, float switch defective etc. To clear the fault message: Up to EPROM Rev. 1.17: switch off machine via main switch. Starting from Rev. 2.00: via ON/OFF button and re-starting the wash cycle (Start button).

FIL 002

Exceeded filling time ­ tank.

AL0

Drain fault ­ wash tank.

AL1

Drain fault ­ prewash tank.

Once the drain time C04 has expired, the float switch must be open. If not: Drain valve defective, drain system clogged, float switch defective etc. Security circuit X8 / 1-2 open: Doors open, reed switches, safety end switch transport actuated (1K8) Input X9 / 1-3 closed ­ check detergent Input X9 / 1-4 closed ­ check rinse aid The connection (RS232) of the two PCBs is broken. Communication fault between the two PCBs There are two possible messages: - - 1 = short circuit / - - 2 = open circuit General temperature fault. General temperature fault.

AL2

Doors fault.

AL3 AL4 -E001 -CF01 F02 F03

Deterget deficiency (option). Rinse agent deficiency (option). Bus system failure Master slave fault Temperature probe "booster" defective. Temperature probe "tank" defective. Temperature probe "prewash tank" defective.

HEATPUMP (Option) AL5 001 Low pressure The compressor has been switched off 4 times within an adjustable time by pressure switch 1B5 (LP). Switching cycle and time control are stored in parameter C24 (= 4) and C42 (= 900 sec). The compressor has been switched off 4 times within an adjustable time by pressure switch 1B5 (HP). Switching cycle and time control are stored in parameter C25 (= 4) and C42 (= 900 sec). Switch on motor protection switch. Up to EPROM Rev. 1.17: eliminate error and switch off the machine via main switch. Starting from Rev. 2.00: switch off machine via ON/OFF button

AL5 002

High pressure

AL5 003

Motor protector compressor tripped

To clear the fault messages AL5 001 and 002:

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NOTES

Page 24 ­ CNA Series (rev. 3.00)

© HOBART GmbH, Service Training Center

SERVICE TRAINING CENTER

NOTES

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CNA Series (rev. 3.00) ­ Page 25

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