Data Sheet for Product

MVS661…N Modulating Refrigerant Valves Technical Instructions
for Ammonia (R717) and Safety Refrigerants Document Number 155-404
May 11, 2016
Siemens Industry, Inc. Page 5
Forced control input ZC
Signal priority
1. Forced control signal ZC.
2. Signal input Y and/or minimum stroke setting with potentiometer Rv possible.
Calibration
The printed circuit board of the MVS661… Series has a slot to facilitate calibration. To
calibrate, insert a screwdriver in the slot so that the contacts inside are connected. As a
result, the valve will first be fully closed and then fully opened.
Calibration matches the electronics to the valve mechanism.
During calibration, the green LED flashes for about 10 seconds; see
Table 4.
Figure 1. Calibration Slot.
NOTE: MVS661..-.. Refrigerant Valves are supplied fully calibrated.
When is calibration
required?
Calibrate after replacing the electronics, when the red LED is lit or flashing, or when the
valve is leaking (at seat).