MKS 651C, Инструкция по эксплуатации, Страница: 159 / 172

Supplement 1 Introduction
Page 3 of 8
Introduction
The optional valve failsafe battery back-up provides full valve drive capability for approximately
30 seconds after an AC power failure.
This supplement provides instructions on how to check your controller to ensure that it recognizes
when the battery back-up module is present, and how to configure the valve position upon a
power loss when using either Local or Remote operation.
Note
For complete, detailed information on the battery back-up option, refer to
Chapter Eight: Valve Failsafe Battery Back-up Option, in Revision E of
the 651C instruction manual.
Battery Voltage
The normal voltage level of the battery ranges from 11 V to 15.5 V. A voltage level below 11 V
indicates a discharged battery. A voltage level above 15.5 V indicates an open fuse, a
disconnected battery, or a defective charger.
Valve Positions
The controller can be configured so that the valve will be driven fully open, fully closed, or will
be disabled upon an AC power failure.
Open: The controller opens the valve at power down. In the event that the valve is already
open, the module provides power for approximately 1 second before turning off.
Closed: The controller closes the valve at power down. In the event that the valve is already
closed, the module provides power for approximately 1 second before turning off.
Disable: The option is disabled and will not perform any function at power down. The
controller turns off in a normal manner.
When the controller is configured to open or close the valve, it will perform the operation
whenever power to the controller is turned off, regardless of whether the power is turned off via
the power switch or by a power failure.
Note
If for any reason the controller cannot open or close the valve within 30
seconds of a power failure, the battery back-up module automatically
turns off. This prevents the battery from discharging when no valve is
present or if the valve is defective in some way.