Safety Interlocks (Limits); Protection Of Safety-Relevant Outputs - Honeywell krom schroder BCU 440 Manual

Burner control unit
Table of Contents

Advertisement

Project planning information

6 .4 Safety interlocks (Limits)

The limiters in the safety interlock (linking of all the rel-
evant safety control and switching equipment for the
use of the application, e.g. safety temperature limiter,
minimum and maximum gas pressure, tightness con-
trol) must isolate terminal 1 from the voltage supply. If
fuse F1 has tripped, this is indicated by a blinking 50
on the display.
If the safety interlocks fail, an immediate program abort
with switch-off of all outputs occurs (even during the
safety time). If the safety interlocks are operational
again or the unit is switched back on, the program run is
restarted in standby.
BCU 440 · Edition 01.17

6 .5 Protection of safety-relevant outputs

When commissioning, do not switch the safety-relevant
outputs to a short-circuit.
Before switching on, ensure that outputs 7 and 12 are
not overloaded (> 3 A), using an ohmmeter, for example.
All safety-relevant outputs of the BCU are fused with an
internal, non-replaceable fuse see, 9 (Connection
diagram). This affects the outputs for ignition and gas
valve V1. In the event that the internal fuse for these
outputs blows, the unit must be sent to the manufac-
turer for repair.
21

Advertisement

Table of Contents
loading

Table of Contents