Parts Breakdown, Thermal Relay Overload, On Button

Thermal Relay Overload

Amp Adjustment Dial: Turn this dial to meet your motor manufacturer's thermal overload amp setting speciﬁcation. Typically this setting is 100-110% of what is listed on the motor data plate as the max amp load. Remember, turning this dial has no effect on increasing motor horsepower. If this dial is turned to an amp setting that is too high, the motor can overheat and be damaged before the relay trips.

Manual Contactor Override Lug: When pushed, the contactor is manually closed for troubleshooting purposes only.

ON Button:

When pushed, power is sent to the magnetic ﬁeld coil and the contactor closes and sends power to the motor.

Reset Button/OFF Button: Reset operation: If the thermal relay has tripped, push this button to reset the thermal relay.

OFF operation: If the motor is operating normally, this button will also cut the current going to the magnetic ﬁeld coil, which opens the contactor and kills

Manual Trip Test Lever:

If the thermal relay function is in question, use a wooden stick

or dowel to slide the brown lever to the right. If the motor shuts off, the thermal relay has tripped and is functional. If the

motor keeps running, the thermal relay contacts are shorted closed and the relay must be replaced.

Parts Breakdown

power to the motor.

3	4	2-2

5	8	7
1		6
		6
		2	2-1
			2-1

REF	PART #	DESCRIPTION

1	PT20550001	SWITCH BOX
2	PT20550002	SWITCH BOX COVER ASSEMBLY
2-1	PT20551002-1	DATA LABEL
2-2	PT20550002-2	PLASTIC COVER SCREW
3	PT20551003	CONTACTOR MA-30 220V
4	PT20550004	FIELD SWITCH

REF	PART #	DESCRIPTION

5	PT20551005	RELAY RA-30 22-34A
6	PT20550006	CONTACTOR RETAINER
7	PS38M	PHLP HD SCR M4-.7 X 10
8	PHTEK18	TAP SCREW #10 X 5/8
10	P4571010	LIQUID-TITE STRAIN RELIEF
11	P4571011	RUBBER SEAL

REPRODUCED IN ANY SHAPE OR FORM WITHOUT THE WRITTEN APPROVAL OF GRIZZLY INDUSTRIAL, INC.

#CR10390 PRINTED IN TAIWAN

Grizzly T20551 Parts Breakdown, Thermal Relay Overload, On Button, Manual Trip Test Lever

Models: T20551