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Siemens Building Technologies
Basic Documentation LMV5...
CC1P7550en
HVAC Products
21 Revision history
13.08.2004
21.3.3
With software version V01.50 or higher, Pt100 sensors
in operating mode 6 are permitted
New load controller function for manipulated variable input and
load output
Manipulated variable input, modulating:
< 3 mA open-circuit
4 mA
or 2 V
low-fire (min. load)
20 mA or 10 V
high-fire (max. load)
Burner shutdown at < 5 mA not used.
Load output, modulating:
< 3 mA Open-circuit
4 mA
0 % load
xx mA Low-fire (min. load)
xx mA High-fire (max. load)
20 mA 100 % load
Shutting the burner down = no impact on signal.
Manipulated variable input, multistage burner:
Stage 1: 5 mA or 2.5 V
Stage 2: 10 mA or 5 V
Stage 3: 15 mA or 7.5 V
Switching thresholds at:
7.5 mA and 12 mA with 0.5 ma hysteresis
3.75 V and 6.25 V with 0.25 V hysteresis
Burner shutdown at < 5 mA not used.
< 3 mA: Open-circuit
Load output, multistage:
Burner off:
4 mA
Stage 1:
5 mA
Stage 2:
10 mA
Stage 3:
15 mA
The load controller’s software has been changed from V01.50 to V01.60.
The following changes have been introduced:
21.3.4
Plausibility check at inputs X61 and X62
The plausibility check at inputs X61 and X62 is not made anymore. This means that fast
value changes at these inputs will no longer result in safety shutdown.
Modulating burners
Multistage burners