FCU 500, FCU 505 · Edition 02.17
80
Parameters
12 .2 .2 High gas pressure protection
Parameter 12
Function of the gas
max.
input (terminal 50)
If the gas pressure exceeds a specified value, the high
gas pressure protection device will prevent a start-up
and trigger a safety shut-down or fault lock-out.
A gas pressure switch DG (high gas pressure protection
device) safeguards the maximum permitted gas pres-
sure. The properties of this function can be activated or
deactivated using parameter 12.
Parameter 12 = 0: OFF; the function is not required
Parameter 12 = 1: with safety shut-down
A safety shut-down will be performed if there is no sig-
nal at the gas
max.
input (terminal 50).
Parameter 12 = 2: with fault lock-out
A fault lock-out will be performed if there is no signal at
the gas
max.
input (terminal 50).
12 .2 .3 Low gas pressure protection
Parameter 13
Function of the gas
min.
input (terminal 49)
The low-pressure cut-off provides verification of the gas
pressure when the fan run-up time t
GV
starts to elapse.
If the gas pressure falls below a specified value, the
FCU performs a shut-down, depending on the function
selected in parameter 13.
Parameter 13 = 0: OFF; the function is not required
Parameter 13 = 1: with safety shut-down
A safety shut-down will be performed if there is no sig-
nal at the gas
min.
input (terminal 49).
Parameter 13 = 2: with fault lock-out
A fault lock-out will be performed if there is no signal at
the gas
min.
input (terminal 49).
