Lamtec VMS 4, Manual

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69
6 Commissioning
6.8.3 Check Shut-Off Limits on VMS Continuous Output
This test is necessary with the use of continuous actuators and with r.p.m.control without the
use of CO/O
2
control affecting these r.p.m.
The usage of O
2
trim can be abandoned, if the excess air of deactivated O
2
trim is higher than
the setpoint.
NOTICE
If a correction affects the continuous channel and if the correction range is bigger than the ad-
justed monitoring band (what is ordinarily the case), the test can be omitted,
Instead of the test, the combustion has to be checked at maximum correctional intervention
(see section 2 ’Checking the O
2
influence’).
The test can also be omitted if the monitoring band is set to 0 at the air deficiency side.
WARNING!
With the adjusted limits towards excess air, it has to be ensured that the flame burns reliably
and stably, and also the flame produces no CO from excess air. If this is not ensured, the
above described inspection has to be executed towards excess air instead of air deficiency.
Turn selector switch (1) to FIRING RATE RATING (firing
rate)
Run to firing rate point to be checked
Wait until the system has run through that point
Turn selector switch (2) to SETTINGS
Adjust setpoint value (4) of the continuous channel in
the air deficiency direction until the actual value feed-
back has changed by the set number of points
(1. monitoring band parameter 62-76)
Check combustion
Reset setpoint value (4) to its origin value
Reset setpoint value (4) to the next continuous channel
in air deficiency direction.
Check combustion
Repeat, until all combustions channels are checked at
their limits.