Cornelius UC 701 service manual Gearmotor, Motor Check

Page 19

GEARMOTOR

The gearmotor is equipped with a start relay and a manual reset overload.

When current is applied, the relay energizes and completes the circuit to the start winding. The motor reaches a predetermined speed and the relay drops out, disconnecting the start winding. The run winding remains in the circuit as long as current is applied.

The purpose of the overload is to automatically shut off the motor in the event of a mechanical bind of the trans- mission, an overload condition within the evaporator or an electrical malfunction. It does this by sensing amper- age draw. If the motor stalls the start relay would energize and stay energized. The amperage would surge 5 to 6 times greater than the normal draw. In this event the overload would shut off the transmission in 4 to 8 sec- onds.

If the motor is subjected to an abnormal load, but does not reach a stall condition, the overload will react, but over a greater period of time. The reaction time depends upon the amperage to which it is subjected.

The overload, through the safety circuit, also shuts off the compressor.

GEARMOTOR

OVERLOAD TRIPPED

Check water level control and evaporator water tube for line build-up restrictions.

NO

CAUTION Clear ice from

evaporator and auger before resetting overload.

Reset overload.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

IMPORTANT

 

 

Icemaker

 

 

 

Resets but

 

 

 

 

 

runs.

 

 

 

 

Icemaker runs when

 

 

 

 

 

motor does

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

not run.

 

reset but problem has

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

not been found.

 

 

 

 

 

 

 

 

 

 

 

Continue checking for

 

 

 

 

 

 

 

 

 

 

 

overload as follows to

 

 

Short run. Trips

 

 

 

 

 

 

guard against future

 

 

again in 2

 

 

 

Resets but

 

problems.

 

 

minutes. Check

 

 

 

 

 

 

 

 

motor does

 

 

 

 

gearmotor circuits.

 

 

 

 

 

 

 

 

 

 

 

 

 

not run.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Check

OVERLOAD GUIDE

 

 

 

 

 

 

 

ELECTRICAL:

 

 

 

 

 

 

 

gearmotor

 

 

 

 

 

 

 

circuits.

SHigh or low voltage. Weak power lines can cause overloads on icemakers restarts.

SHigh running current (2.4amps or above). Check motor circuits and start relay.

SAuger delay failed.

ICEMAKER

SMechanical parts worn. Scored evaporator or auger. Worn thrust bearing.

SIcemaker not turning off. Failed ice level control.

SOver compression. Low water inlet temperature. Restrictions in water line from reservoir.

REFRIGERANT

SContaminated charge or bad compressor.

SLow charge or gas leak.

SLow suction pressure. Improper expansion valve. Sensing bulb location or insulation and/or defective expansion valve.

YES

CLEAN

See Instructions.

Will not

Reset.

Overload

hot try again.

Will not reset.

Replace overload.

MOTOR CHECK

The resistance readings on the winding will be between 5 to 25 ohms. A meter capable of these low readings must be used. The start relay cover must be removed. (See Figure 7).

If no continuity on start or run winding test, replace gearmotor. If continuity on grounded motor test, replace gearmotor.

630460150

16

Image 19
Contents UC 701 Series CONTINUOUS-FLOW Icemaker Table of Contents Table of Contents cont’d Follow Safety Instructions Safety InformationRecognize Safety Information Understand Signal WordsThis page Left Blank Intentionally Claims Instructions General DescriptionTo the User of this Manual DescriptionSpecification Chart Clearance Requirements This page Left Blank Intentionally PRE-INSTALLATION InstallationSide Bracket Installation InstallationIcemaker Float Assembly Initial Start UP, Checks and Adjustment InstructionsThis page Left Blank Intentionally Monthly Guide to ServiceIcemaker Cleaning and Sanitizing Procedures MaintenancePurpose Water Level ControlSemi-Annually How Water Level Control WorksTo Replace Water Level Control Refrigeration System AdjustmentsTo Replace Water Level Safety Switch Refrigeration SystemExpansion Valve Adjustment and TroubleshootingCondenser Modulating Valve BIN Control Condenser Modulating Valve RemovalMotor Check GearmotorStart Relay To Replace Gearmotor AssemblyAuger and Extruding Head Removal Upper NUT and Bearing AssemblyTo Replace Bearing Capacitor Check Electrical CheckoutGear Motor Overload Safety ControlsGuide to Good ICE Wiring Diagram Troubleshooting Chart Icemaker not Operating Troubleshooting Compressors TroubleshootingIMI Cornelius Certificate of WarrantyThis page Left Blank Intentionally IMI Cornelius INC