Honeywell S7999D1048 - Page 61

S7999D1048 COMBUSTION SYSTEM OPERATOR INTERFACE DISPLAY
61 65-0321—01
Setpoints:
Modulation (0-500°F or 0-750 psi)
On-Off (0-500°F or 0-750 psi)
Low Fire Hold (0-500°F or 0-750 psi)
APPLICATION NOTE
Application: Water Temperature Load Control
Description: On-off and modulating outputs to start/stop and adjust firing rate to maintain a control
setpoint.
M24241
LOW FIRE
HOLD CONTROL
CIRCUIT
FIRING RATE
MOTOR
INTERFACE
MODBUS COMMUNICATION
HONEYWELL S7810M
L1
ON–OFF CONTROL
BURNER CONTROL
L1
D+
+
-
+
-
R
D-SHIELD
26
27
25
21
19
17 1816
5
9
8
6
L2
L1
G
C A B
L1
L2
RTD SENSOR
100 OHM
UDC
CONTROLLER
Digital Inputs: None Digital Outputs: On-Off relay
Optional: Modulation Alarm1 (ON
when at or below Modulation setpoint,
OFF when above Modulation setpoint)
Optional: Low Fire Hold Alarm2 (ON
when at or below Low Fire Hold
setpoint, OFF when above Low Fire
Hold setpoint)
Analog Inputs:
Vessel water sensor
temperature (0-500°F) (100

RTD)
Analog Outputs:
PID modulation (4-20mA) to control
firing rate. Modulation based on
modulation setpoint.
Application File:
temp01.nge temp02.nge temp03.nge temp04.nge
Range
0–300°F 0–300°F
LOW FIRE HOLD
0–500°F 0–500°F
LOW FIRE HOLD
Controller
Model (see
footnote)
1212