Electrical Connection Of Ionization Probe And Flame Detector; Commissioning Notes - Siemens LMV50 Series Manual

Building Technologies
1.4 Electrical connection of ionization probe and
flame detector
It is important to achieve practically disturbance- and loss-free signal transmission:
∂
Never run the detector cables together with other cables
– Line capacitance reduces the magnitude of the flame signal
– Use a separate cable
∂
Observe the permissible cable lengths
∂
The ionization probe is not protected against electrical shock. The mains-powered
ionization probe must be protected against accidental contact
∂
Locate the ignition electrode and the ionization probe such that the ignition
spark cannot arc over to the ionization probe (risk of electrical overloads)

1.5 Commissioning notes

∂
When commissioning the plant, or when doing maintenance work, make the
following safety checks:
Safety checks to be carried out
a) Start the burner with the flame detector
darkened
b) Start the burner with the flame detector
exposed to extraneous light, e.g. to
incandescent light with detectors for
infrared or visible radiation (with QRI,
interrupted at about 20 Hz), quartz-
halogen bulb or cigarette lighter flame
with detectors for UV radiation (QRA7)
c) Simulate loss of flame during operation.
For that, darken the flame detector in the
operating position and maintain that state
d) Check the plant's response time with loss
of flame during operation. For that
purpose, manually disconnect the fuel
valves from power and check the time
from this moment the burner control
requires to switch off power to the valves
∂
There is no absolute protection against incorrect use of the RAST5 connectors. For
this reason, prior to commissioning the plant, check the correct assignment of all
connectors
∂
Electromagnetic emissions must be checked on an application-specific basis
∂
Make a loss-of-flame test using the AZL5 of the LMV5
Basic Documentation LMV5...
1 Safety notes
Expected response
Lockout at the end of the
safety time
Lockout at the end of the
prepurge time
Β
Note:
Only when supervision of
extraneous light is activated!
Lockout or restart, depending
on the burner control's
configuration
Burner control turns off power
to the valves within the period
of time permitted for the
respective type of plant
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CC1P7550en
22.05.2018