AERCO BMS 168 - Manual (Page 51)

A-3
Appendix A
(cont.)
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BOILER DRIVE
Drive Type (PWM) Signal
(with 12 msec time base)
Optically-isolated, pulse width modulated
Valve drive 100% fire rate at 95% pulse width, 0% fire rate at
5% pulse width
Current Loop Determination Optically isolated detection
MEMORY
Non-Volatile Memory
EPROM storage of system input. Variables
changed in Field Adjust or Configure System
mode. EPROM storage of on/off state. All other
variables stored in volatile memory which is not
retained after power interruption.
ALARMS
Error Handling
If a valid error condition occurs, the display will
show the error condition for 2 seconds, then return
to the previous display. If multiple error conditions
are present, the display will show all error modes.
The alarm relay contacts will close upon detection
of the error. The alarm can be canceled by
pressing the RESET RATIO key or correcting the
error.
Error Messages Refer to Appendix H for displayed error messages
and troubleshooting information.