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OM 750
Remote Shutdown Input Signal
This input allows a single set of dry-contacts to be used to signal the
UVC to go into shutdown mode. When the contacts close (shutdown)
the UVC will go into shutdown mode, when the contacts open the UVC
will return to normal operation. See Special Purpose Unit Modes.
EXTERNAL BINARY INPUT 3
This input can be configured as a ventilation lockout (default) or
exhaust interlock signal.
Ventilation Lockout Input Signal
This input allows a single set of dry-contacts to be used to signal the
UVC to close the OA damper. When the contacts close (ventilation
lockout signal) the UVC will close the OA damper, when the contacts
open the UVC will return to normal OA damper operation.
Exhaust Interlock Input Signal
This input allows a single set of dry-contacts to be used to signal the
UVC that an exhaust fan within the space has been energized, the UVC
will reposition the OA damper to a user adjustable minimum position
(Exhaust Interlock OA Damper Min Position Setpoint). When the
contacts close (exhaust fan on signal) the UVC will use the value
defined by the Exhaust Interlock OA Damper Min Position Setpoint as
the minimum OA damper position regardless of IA fan speed, when the
contacts open the UVC will return to normal OA damper operation.
External Binary Outputs
The UVC is provided with three (3) binary outputs which can provide
the following functions. These outputs are relay type outputs which are
intended to be used with signal level voltages (24vac max) only. For
wiring see MicroTech II Unit Ventilator Controller IM747.
Not all of the functions listed can be used at the same time. The
UVC is provided with configuration parameters which can be
adjusted to select which function will be used for these outputs
when multiple functions are indicated below.
NOTICE
EXTERNAL BINARY OUTPUT 1
This output can only be used as a signal for space lights.
Lights On/Off Signal
This relay output provides one set of NO dry-contacts which can be
used to signal the operation of the space lights. When the UVC is in
occupied, standby or bypass occupancy modes the relay output will
signal the lights on (contacts closed), when the UVC is in unoccupied
occupancy mode the relay output will signal the lights off (contacts
open).
EXTERNAL BINARY OUTPUT 2
This output can only be used as a fault signal.
Fault Signal
This relay output provides a NO, NC, and Common connections that
can be used to signal a fault condition. When a fault exists, the UVC
will energize this relay output, when the fault or faults are cleared the
UVC will de-energize this relay output.
EXTERNAL BINARY OUTPUT 3
This output can only be used to signal exhaust fan operation.
Exhaust Fan On/Off Signal
This relay output provides one set of NO dry-contacts which can be
used to signal the operation of an exhaust fan. When the OA damper
opens more than the Energize Exhaust Fan OA Damper Setpoint then
the relay output will signal the exhaust fan on (contacts closed), when
the OA damper closes below this setpoint the relay output will signal
the exhaust fan off (contacts open).