Emerson VSS, VSR, VSM service manual Operation, Vss / Vsr / Vsm Command Shaft Rotation And Travel

Operation

The Motor Amps Load Limit protects the com- pressor from overloading by decreasing the compressor capacity if the motor amperage is at the Maximum Amps setpoint, or preventing an increase in capacity if the motor amperage is above the Full Load Amps setpoint. ( See manual for the appropriate microprocessor.)

3. Oil Separator Heater

The oil separator heater keeps the oil in the separator from becoming too viscous and helps keep gas from condensing in the receiver section of the separator.

The heater is turned on only when the compres- sor is off. The separator heater is supplied with an integral temperature control.

B. Safety Setpoints

A detailed explanation of all safety setpoints can be found in the Compact Logix PLC manual, p/n 35391CL.

1. Oil Pressure

Low oil pressure differential stops the compressor unit when there is an insufficient difference in pres- sure between the oil manifold and suction.

2. Discharge Pressure

High discharge pressure cutout stops the compres- sor unit, when the discharge pressure in the oil separator exceeds the setpoint.

	TABLE 1.		VSS / VSR / VSM COMMAND SHAFT ROTATION AND TRAVEL
	COMMAND SHAFT ROTATION				NO. OF TURNS / ROTATION ANGLE / SLIDE TRAVEL
COMP.	CAPACITY		VOLUME		CAPACITY				VOLUME
MODEL	INC	DEC	INC	DEC	TURNS/ANGLE/TRAVEL			TURNS/ANGLE/TRAVEL
VSS 291	CW	CCW	CW	CCW	0.91 /	328	/ 3.568”	0.52	/	187	/ 2.045”
VSS 341	CW	CCW	CW	CCW	0.91 /	328	/ 3.568”	0.52	/	187	/ 2.045”
VSS 451	CW	CCW	CW	CCW	0.91 /	328	/ 3.568”	0.52	/	187	/ 2.045”
VSS 601	CW	CCW	CW	CCW	0.91 /	328	/ 3.568”	0.52	/	187	/ 2.045”
VSS 751	CCW	CW	CCW	CW	1.09 /	392	/ 4.283”	0.63	/	227	/ 2.473”
VSS 901	CCW	CW	CCW	CW	1.09 /	392	/ 4.283”	0.63	/	227	/ 2.473”
VSS 791	CCW	CW	CCW	CW	1.22 /	439	/ 4.777”	0.74	/	266	/ 2.889”
VSS 891	CCW	CW	CCW	CW	1.22 /	439	/ 4.777”	0.74	/	266	/ 2.889”
VSS 1051	CCW	CW	CCW	CW	1.22 /	439	/ 4.777”	0.74	/	266	/ 2.889”
VSS 1201	CCW	CW	CCW	CW	1.22 /	439	/ 4.777”	0.74	/	266	/ 2.889”
VSS 1301	CCW	CW	CCW	CW	1.22 /	439	/ 4.777”	0.74	/	266	/ 2.889”
VSS 1501	CCW	CW	CCW	CW	1.36 /	490	/ 5.325”	0.82	/	295	/ 3.200”
VSS 1801	CCW	CW	CCW	CW	1.36 /	490	/ 5.325”	0.82	/	295	/ 3.200”
VSM 71	CW	CCW	CW	CCW	0.80 /	288	/ 3.141”	0.45	/	162	/ 1.767”
VSM 91	CW	CCW	CW	CCW	0.80 /	288	/ 3.141”	0.45	/	162	/ 1.767”
VSM 101	CW	CCW	CW	CCW	0.80 /	288	/ 3.141”	0.45	/	162	/ 1.767”
VSM 151	CW	CCW	CW	CCW	0.80 /	288	/ 3.141”	0.45	/	162	/ 1.767”
VSM 181	CW	CCW	CW	CCW	0.80 /	288	/ 3.141”	0.45	/	162	/ 1.767”
VSM 201	CW	CCW	CW	CCW	0.80 /	288	/ 3.141”	0.45	/	162	/ 1.767”
VSM 301	CW	CCW	CW	CCW	0.80 /	288	/ 3.141”	0.45	/	162	/ 1.767”
VSM 361	CW	CCW	CW	CCW	0.80 /	288	/ 3.141”	0.45	/	162	/ 1.767”
VSM 401	CW	CCW	CW	CCW	0.80 /	288	/ 3.141”	0.45	/	162	/ 1.767”
VSM 501	CCW	CW	CCW	CW	0.91 /	328	/ 3.568”	0.52	/	187	/ 2.045”
VSM 601	CCW	CW	CCW	CW	0.91 /	328	/ 3.568”	0.52	/	187	/ 2.045”
VSM 701	CCW	CW	CCW	CW	0.91 /	328	/ 3.568”	0.52	/	187	/ 2.045”

NOTE: These refer to the old style gear motors and DO NOT apply to the new optical motors.Rotation for the optical motors is the OPPOSITE of what is shown in the chart.

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