Setting The Fan Parameters During Startup And Shutdown - Siemens LMU54 Series Basic Documentation

Setting the fan parameters
during startup and shutdown
Parameter LMU...
Speed Signal
-1
[min ] PWM [%]
NoG_MAX
N_VL* LmodVL*
(N_VL_Delta)
N_VL_QAA* LmodVL_QAA*
PhzMax
NhzMax
N_Vor LmodVor
(N_Vor_Delta)
(N_ZL_Delta)
N_Nachstell_Delta
N_ZL* LmodZL*
N_Nachstell_Delta
(N_ZL_Delta)
LmodZL_QAA*
N_ZL_QAA*
N_TL* LmodTL*
(N_TL_Delta)
N_TL_QAA* LmodTL_QAA*
LmodNull
NoG_Null
* Depending on parameter «FaEinstellFlags3»
Siemens Building Technologies
HVAC Products
To visualize the following description, also refer to the sequence diagram of the LMU...
and the following graph.
Boiler
MAX
Heating
MAX
MIN
OFF
Boiler
Fan control and speed parameters
First, set the speed limits while speed readjustment is switched off.
For that purpose, set the fan control parameters («LmodZL», «LmodVor», etc.) to the
values required from the combustion point of view (with the medium flueway and at
mains voltage).
Then, also determine the associated fan speeds from the fan characteristic and
parameterize them accordingly («N_ZL», «N_Vor», etc.).
In a first approach, set the limit values for the permitted bands very wide
(«N_ZL_Delta», «N_Vor_Delta», etc.).
The values of fan control and fan speed can now be optimized.
Speed limits
First, the speed readjustment should be set to the required or parameterized speed
readjustment.
When the optimization or setting is completed, proceed to the next step and determine
and set the speed limits.
For that purpose, use the PC tool and record the speed (Gebl_F_Drehz) in a startup and
shutdown cycle under the following boundary conditions:
1. With the minimum flueway and undervoltage (AC 195 V)
2. With the maximum flueway and overvoltage (AC 253 V)
Now, set the speed bands (speed limits about the selected speeds, that is, «N_ZLV +/-
N_ZL_Delta», etc.) such that in all possible worst cases, the measured speed lies within
the valid band (see above).
Faults outside these worst cases give rise to a violation of the speed limits and lead to
appropriate reactions (refer to sequence diagram).
Basic Documentation LMU54... / LMU64...
3 Functions
Extra function «Speed readjustment»
(optional)
Speed limitation
KonfigRg5)
N_Nachstell Kon1
N_Nachstell_Lern
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CC1P7494en
07.11.2002