Safety Limits; Safety Time During Operation - Honeywell Krom Schroder BCU 580 Technical Information

Parameters

10 .5 Safety limits

Parameter 19 can be used to adjust the safety limits
(safety time during operation) to the system require-
ments.

10 .5 .1 Safety time during operation

Parameter 19
Parameter 19 = 1; 2: time in seconds.
The safety time during operation is the time that the
BCU needs to stop the fuel supply after a flame failure
during operation or an interruption at the safety current
inputs (terminals 45 to 51 and 65 to 68). The safety
time can be set to 1 or 2 s. Prolonging the safety time
during operation increases the installation availability
in the case of brief-duration signal fades (e.g. fades of
the flame signal).
In accordance with EN 298, the maximum reaction
time to a flame failure must not exceed 1 s. In accord-
ance with EN 746-2, the safety time of the installation
during operation (total closing time) may not exceed 3 s.
The requirements of national standards and regulations
must be satisfied.
BCU 580 · Edition 11.15l 74