Assignment Of Connection Terminals - Honeywell BCU 460 Technical Information

Function

3 .2 .8 Assignment of connection terminals

Terminal Type
1
2
3
4
Control input
(AC mains voltage)
6
7
35
39
40
Safety circuit input
(AC mains voltage)
41
22
Input (�A)
23
52, 53 Output
54, 24
57, 27,
36
Voltage supply +
safety circuit input
58, 28,
(AC mains voltage)
37
59, 38
BCU 460, BCU 465 · Edition 11.19
Designation
Start-up signal
Remote reset
External purge air
External air valve control
High temperature operation
feedback
Flameless operation (Low NO
x
mode) feedback
Controller enable/Emergency
stop
LDS query
Feedback from actuator
Feedback from actuator
Flame signal 1 (pilot burner)
Flame signal 2 (main burner)
UV sensor
UV sensor for continuous
operation
Minimum air pressure
Minimum air pressure
Valve proving system
Function
Signal applied: heating start; no signal: heating stop
Input for external signal (button) to reset the unit after a fault lock-out. System faults
(internal errors) can only be acknowledged using this button.
If there is an active signal, the BCU opens the air actuator regardless of the status of the
other inputs.
External air valve control with an active signal, e.g. to supply air to the combustion chamber
for cooling. Controlled air flow is only possible in standby with deactivated start-up signal.
As soon as heating operation is started (start-up signal at terminal 1), the function is
interrupted.
High temperature operation feedback input. When the input is activated, the BCU operates
without evaluating the flame signal. The safety function of the device's internal flame
control system is deactivated.
Low NO mode feedback input. When the input is activated, the BCU operates without
x
evaluating the flame signal. The safety function of the device's internal flame control
system is deactivated. The furnace chamber temperature is monitored by a safety
temperature monitor (STM).
Connection for higher-level safety devices and interlocks (e.g. emergency stop)
Feedback signal of the control element position for ignition capacity. As soon as a signal is
present, the BCU completes a burner start, restart or start-up attempt.
Feedback input for ignition position
Feedback input for maximum capacity
Connection for flame rod/UV sensor/ignition transformer
Connection for flame rod/UV sensor/ignition transformer
Supply voltage for UV sensor UVS
Voltage supply for UV sensor UVC 1
Connection for sensor 1 with pilot lamp to monitor the air pressure
Connection for sensor 2 with pilot lamp to monitor the air pressure
Connection for the sensor of the valve proving system (tightness control pressure switch or
POC switch for checking the closed position)
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28