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 3
Operator controls and
indicators in the
electronics housing
1 Connection terminals
2 LED for indication of operating state
3 Minimal stroke setting potentiometer Rv
4 Auto-calibration
5 DIP switches for mode control
Replacement Parts
If the valve’s electronics become faulty, the entire electronics housing must be replaced by
spare part ASR61, which is supplied with Mounting Instructions (74 319 0270 0).
If the installation is resized, or if excessive wear impacts the valve’s
performance, a new valve insert (ASR…N) will restore the valve’s
characteristics to its original specifications.
The valve insert is supplied complete with Mounting Instructions
(74 319 0486 0).
Technical Design/
Functions
Features and Benefits
 Four selectable control signals for setpoint and measured value.
 DIP switch to reduce the C
V
(k
vs
) value to 63% of the nominal value.
 Potentiometer for adjustment of minimum stroke for suction throttle applications.
 Automatic stroke calibration.
 Forced control input for “Valve closed” or “Valve fully open”.
 LED for indicating the operating state.
Control
The MVS661… Series refrigerant valve can be driven by Siemens or third-party
controllers that deliver a 0/2 to10 Vdc, or 0/4 to 20 mA output signal.
For optimum control performance, use a 4-wire connection between the controller and
valve. The valve stroke is proportional to the control signal.
The valve stroke is proportional to the control signal.
CAUTION:
You must use a four-wire connection with Vdc power supply.
Spring return action
If the control signal is interrupted, or in the event of a power failure, the valve’s return
spring will automatically close control path.