Red Lion TSC - Manual (Page 41)

Alarm Hysteresis (AHYS)
The alarm(s) values have a programmable hysteresis band to prevent alarm
output chatter near the alarm trigger temperature. The hysteresis value should
be set to eliminate this effect. A value of 2 to 5° is usually sufficient for most
applications. A single alarm hysteresis value applies to both alarms.
Refer to the alarm action figures for the effect of hysteresis on the various
alarm types.
AHYS - 1 to 250 degrees
COOLING OUTPUT PARAMETERS MODULE (5-02)
(OPTIONAL)
The optional secondary output (OP2) operates as an independent cooling
output for systems that use heating and cooling. One of the three types of
output modules (Relay, Logic/SSR Drive or Triac) must be ordered separately
and installed into the cooling channel socket.
Note: Units with the RS-485 serial communications option must have the same
type of modules installed for the cooling output and alarm output.
The output modules may be replaced or interchanged (with appropriate
wiring considerations) at any time without re-programming the controller.
The front panel indicator OP2 illuminates when the cooling output is on. (See
Output Module “OUTPUT ON” State Table for definition, under installing
output modules section). Cooling output power is defined as ranging from
-100% (full cooling) to 0% (no cooling, unless a heat-cool band overlap is used).
Cooling Cycle Time (CYC2)
A value of 0 turns off the cooling output, independent of cooling power
demand.
CYC2 - 0 to 120 seconds
Cooling Relative Gain (GAN2)
This parameter defines the gain of the cooling band relative to the heating
band. A value of 0.0 places the cooling output into ON/OFF control mode with
the Heat-Cool parameter (db-2) becoming the cooling output hysteresis. This
may be done independent of the main output control mode (PID or ON/OFF).
Relative gain is generally set to balance the effects of cooling to that of heating
for best control.
GAN2 - 0.0 to 10.0
Example: If 10 kW of heating and 5kW of cooling is available, initially set the
cooling gain to (2.0). The heat/cool operation figure illustrates the effect of
different gains.
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