7
External Target Temperature Input and
Override with Primary Piping
Mode 6 (Mode = 6)
(Not Supported)
Mode 6 is designed for a 0-10VDC or a 4-20 mA exter-
nal input signal and override operation using Primary
Piping. The external input signal creates an internal
CFH and changes the heater target according to a lin-
ear scale. The control stages the heater to maintain
the heater target at the heater outlet sensor.
External Target Temperature Input and
Override with Primary/Secondary Piping
Mode 7 (Mode = 7)
Mode 7 is designed for a 0-10VDC external input sig-
nal and override operation using Primary/Secondary
Piping. The external input signal can be provided from
a Building Management System. The override can be
used to heat an indirect domestic hot water tank.
The external input signal creates an internal CFH and
changes the heater target according to a linear scale.
The control stages the heater to maintain the heater
target at the heater outlet sensor.
Once an indirect DHW override is present, the control
stages the heater to maintain the heater target at the
heater system sensor. If both an external input signal
and an indirect DHW override are present at the same
time, the control operates at the higher of the two tar-
gets.
500 Ω
GND
HOT
GND
HOT
0-20
mA INPUT
0-20
mA INPUT
500 Ω
Fig. 13: 500
Ω
Resistor for 4-20 mA Operation
NOTE:
To convert a 0-20 mA input signal to 0-10
VDC, a 500 Ω resistor must be added. See Fig. 13.
External Direct Drive Operation
Mode 8 (Mode = 8)
Mode 8 is designed for a 0-10VDC or a 4-20 mA exter-
nal input signal from a building management system or
external sequence, such as the
Raypak Temp-
Tracker Mod+ Hybrid
, to drive the staging rate
directly with either Primary or Primary/Secondary pip-
ing. The indirect DHW override is disabled.
The control receives a CFH and analog signal provid-
ed from an external control. The control stages the
heater according to the input signal. The maximum
outlet temperature is controlled by DIP switch “A.”
Fixed Heater Outlet Maximum: 200°F (“A” = “ON”)
235°F (“A” = “OFF”)
Fig. 12: External Input Target Temperature and Setpoint
Operation, Primary-Secondary Piping (Mode 7)
Fig. 14: External Direct Drive Operation (Mode 8)
