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If the modulation rate is greater than 25% at the Begin Setback period (
BEGIN STBCK
) when the
PPC4000 is scheduled to operate according to the reduced setback setpoints, the PPC4000 will delay
opening the operating control output until the servo motors reach the low fire position, P03.
SETBACK OVERRIDE:
In addition, the PPC4000 provides the ability to program a digital input
to override the setback mode of the PPC4000 control for a programmed period of time from 1 to 8
Hours (
OVERRIDE HOURS
). If the PPC4000 is operating in the setback mode and the digital
input is active (set to SETBACK OVERRIDE) and momentarily closed then opened, the PPC4000
will exit the setback mode and control according to the steam pressure (or water temperature) set-
point (
SETPOINT 1
or
SETPOINT 2
) for the programmed period of time (1 to 8 Hours). If the con-
tact is closed and opened BEFORE the programmed time period expires, the PPC4000 will return to
the setback mode.
FORCED SETBACK:
The PPC4000 provides a programmable digital input to force the PPC4000
to operate according to its setback setpoints for as long as this contact is closed, regardless of the pro-
grammed setback schedule.
FORCED SETBACK
has highest priority.
STANDBY WATER
Only Sensor 2 can be used to maintain the boiler in a standby condition. Sensor 2 can be configured
to use either a temperature or pressure sensor. The normal configuration would be for Sensor 1 to be
a pressure sensor and Sensor 2 to be a temperature sensor so a lower than boiling point temperature
can be maintained in the boiler. The following setup shows how to do that.
Install a temperature sensor to the Sensor 2 input and configure it in the following manner:
SENSOR 2 SETUP menu:
SENSOR TYPE:
STANDBY
SENSOR RANGE:
(user set to currently installed temperature sensors)
SETPOINT 2 SETUP menu:
SENSOR USED:
2
SETPOINT:
(set by user to the desired standby water temperature)
NORMAL OPERATING SETPOINTS
SETBACK SETPOINTS
SETPOINT 1 = 100 PSI
SETBACK = USED
STBCK SUN = ALL STBCK
END STBCK = 0:800AM
STBCK MON=SCHEDULE
BEGIN STBCK = 5:00PM
STBCK TUE=SCHEDULE
STBCK STEAM = 50 PSI
STBCK WED=SCHEDULE
STBCK THU=SCHEDULE
STBCK FRI=SCHEDULE
STBCK SAT = NO STBCK
SUN
MON
TUE
WED
THU
FRI
SAT
SUN
50 PSI
100
8:00A
5:00P
8:00A
5:00P
8:00A
5:00P
8:00A
5:00P
8:00A
5:00P
12:00A
12:00A
STEAM PRESSURE
