Trane Voyager Commercial, Installation, Operation And Maintenance Manual

Page: 60 / 156

60 RT-SVX34R-EN
heating is removed, the fan will remain on for
approximately 90 seconds.
Electric Heat Control
The RTRM provides two heating outputs for 1st and
2nd stages that will be controlled with at least a 10
seconds delay between each stage. When the fan
selection switch is in the “
“A AU UT TO O” ” mode and the unit is
configured for Constant Volume, the fan will start
approximately 1 second before the 1
st
heater stage is
activated. The fan and heater will cycle off after the
heating setpoint has been satisfied. If the unit is
configured for SZ VAV control, the Supply Fan will
energize approximately 5 seconds prior to energizing
the electric heat outputs. Once the Zone Heating
requirements have been satisfied, the fan and heat
outputs will be controlled off.
Clogged Filter Option
The unit mounted clogged filter switch monitors the
pressure differential across the return air filters. It is
mounted in the filter section and is connected to the
RTOM. The switch is adjustable and can be set for a
particular application. The clogged filter switch is
normally open and will automatically close when the
pressure differential across the filters falls below the
clogged filter setpoint. The RTOM will generate a
SERVICE diagnostic that will be sent to the zone sensor
or remote panel when the clogged filter switch has
been closed for at least 2 minutes during supply fan
operation. The system will continue to operate
regardless of the status of the clogged filter switch.
Ventilation Override
N No otte e:: Applying 24 volts to one of the three Ventilation
Override Inputs manually activates ventilation
override. One input is provided to request the
Pressurize Mode, the second input the Purge
Mode, and the third input the Exhaust Mode.
When the Pressurize Mode is selected, activating
Ventilation Override will cause the supply fan to run,
the economizer to open to 100%, the exhaust fan to
turn (remain) off, or the VFD to run at full speed (SZ
VAV and Traditional VAV), and the VAV boxes to fully
open.
When Purge is selected, activating Ventilation Override
will cause the supply fan to run, the economizer to
open to 100%, the exhaust fan to run, or the VFD to run
at full speed (SZ VAV or Traditional VAV), and the VAV
boxes to fully open.
When Exhaust is selected, activating Ventilation
Override will cause the supply fan to turn off, the
economizer to close to 0%, the exhaust fan to run
(exhaust damper at 100% if configured for Statitrac), or
the VFD to stop, and the VAV boxes to operate
normally.
If more than one mode is requested at the same time,
the Pressurize request will have priority followed by
Purge. When any Ventilation Override Mode is active,
all heating and cooling is turned off. For the case where
the unit is required to turn off, the Emergency Stop
input is used. The ICS can also initiate any ventilation
override mode.
Table 35, p. 60 lists the sequence of
events within the system for each ventilation mode.
Refer to the unit wiring diagram for contact switching
and wiring.
N No otte e:: Fresh air tracking will not work with VOM.
Table 35. Ventilation override sequence
Affected
Function
Mode and Priority
Pressurize
Purge
Exhaust (a)
1 2 3
Heat/Cool
off off off
VFD full speed full speed full speed
Supply Fan on on off
Exhaust Fan off
on (b)
on
Economizer
open open
closed
VAV Boxes
forced open forced open
normal
operation
(a) Exhaust mode 3 is not available with the tracking power exhaust
option.
(b)
For units configured with the Statitrac option, the Exhaust Damper
will open during Ventilation Override modes that request the ex-
haust fan to operate.
Emergency Stop
When this binary input is opened, all outputs are
immediately turned off and the system will not be
allowed to restart until the binary input is closed for
approximately 5 seconds minimum. The shut down is
communicated to Tracer
™ if applicable and the Heat
and Cool LED outputs (RTRM J6-7 and J6-8) will blink
at a nominal rate of 1 blink per second.
Phase Monitor
The Phase Monitor is a 3 phase line monitor module
that protects against phase loss, phase reversal and
phase unbalance. It is intended to protect compressors
from reverse rotation. It has an operating input voltage
range of 190-600 VAC, and LED indicators for ON and
FAULT. There are no field adjustments and the module
will automatically reset from a fault condition.
Low Pressure Control
This input incorporates the low pressure cutout of each
refrigeration circuit and can be activated by opening a
field supplied contact.
If this circuit is open before a compressor(s) is started,
neither compressor in that circuit will be allowed to
operate.
S Stta arrttu up p