General Information
RT-SVX46G-EN
9
approximately 0.8' wc and open when the
differential falls to 0.7-inch wc.
Compressor Disable (CPR1/2)
This input incorporates the low pressure control (LPC) of
each refrigeration circuit and can be activated by opening
a field supplied contact installed on the LTB.
If this circuit is open before the compressor is started, the
compressor will not be allowed to operate. Anytime this
circuit is opened for 1 continuous second during
compressor operation, the compressor for that circuit is
immediately turned “Off”. The compressor will not be
allowed to restart for a minimum of 3 minutes should the
contacts close.
If four consecutive open conditions occur during the first
three minutes of operation, the compressor for that circuit
will be locked out, a diagnostic communicated to the
remote panel (if installed), and a manual reset will be
required to restart the compressor.
Compressor/Inverter Protection
The ReliaTel™ control receives input from the inverter
drive for any errors encountered by the drive (refer to RT-
SVD05*-EN and RT-SVD007*-EN for VF-S15 inverter error
code details). If an error is encountered before the
compressor has run for 3 minutes, ReliaTel™ begins
counting errors. The drive will automatically reset when
the error condition clears and ReliaTel™ will try to start the
compressor again, if a call for cooling remains and 3
minutes have passed since the compressor last ran.
If ReliaTel™ counts 4 such errors within 30 minutes, the
system will go to manual lock out mode. Refer to RT-
SVD05*-EN (for VF-S15 inverters, refer to RT-SVD007*-
EN) for potential causes.
Condensate Drain Pan Overflow Switch
(Optional) - ReliaTel™
This input incorporates the Condensate Overflow Switch
(COF) mounted on the drain pan and the ReliaTel™
Options Module (RTOM). When the condensate level
reaches the trip point for 6 continuous seconds, the RTOM
will shut down all unit functions until the overflow
condition has cleared. The unit will return to normal
operation after 6 continuous seconds with the COF in a
non-tripped condition. If the condensate level causes unit
shutdown more than 2 times in a 3 days period, the unit
will be locked-out of operation requiring manual reset of
diagnostic system through Zone Sensor or Building
Automation System (BAS). Cycling unit power will also
clear the fault.
Discharge Line Temp Switch (DLTS)
The DLTS is looped in series with HPC and LPC. It prevents
compressor from overheating (over 300º F dome temp) in
case of indoor fan failure (cooling) or outdoor fan failure
(heating).
Duct Mounted Relative Humidity Sensor
(BAYSENS037*)
Field installed, duct mounted humidity sensor is used to
control activation of enhanced dehumidification and the
hot gas reheat dehumidification options. Humidity set
points can be selected for relative humidity levels between
40% and 60% by adjusting the DEHUMID setting on the
ReliaTel™ options module. See
.
Economizer Control Actuator (Optional) -
ReliaTel™ Control
The ECA monitors the mixed air temperature, return air
temperature, minimum position setpoint (local or
remote), power exhaust setpoint, CO
2
setpoint, CO
2
, and
ambient dry bulb/enthalpy sensor or comparative
humidity (return air humidity against ambient humidity)
sensors, if selected, to control dampers to an accuracy of
+/- 5% of stroke. The actuator is spring returned to the
closed position any time that power is lost to the unit. It is
capable of delivering up to 25 inch pounds of torque and
is powered by 24 Vac.
Evaporator Frost Control (Standard)
This input incorporates the Frostat™ control (FOS)
mounted in the indoor coil circuit and can be activated by
closing a field supplied contact installed in parallel with
the FOS.
If this circuit is closed before the compressor is started, the
compressor will not be allowed to operate. Anytime this
circuit is closed for 1 continuous second during
compressor operation, the compressor for that circuit is
immediately turned “Off”. The compressor will not be
allowed to restart for a minimum of 3 minutes should the
FOS open.
Frostat™ is standard on single zone VAV products
(SZVAV).
High Pressure Control - ReliaTel™ Control
The high pressure controls are wired in series between the
compressor outputs on the VSM and the compressor
contactor coils (3 to 5 ton eFlex™) or compressor drive (7.5
to 10 ton eFlex™). If the high pressure control switch
opens, the VSM senses a lack of current while calling for
cooling and locks the compressor out.
If four consecutive open conditions occur during an active
call for cooling, the compressor will be locked out, a
diagnostic communicated to ICS™, if applicable, and a
manual reset required to restart the compressor. On dual
compressor units only the affected compressor circuit is
locked out.
High Temperature Sensor (BAYFRST001*)
This sensor connects to the RTRM Emergency Stop Input
on the LTB and provides high limit “shutdown” of the unit.
The sensor is used to detect high temperatures due to a
high thermal event in the air conditioning or ventilation
ducts. The sensor is designed to mount directly to the
