ZIEHL-ABEGG Econtrol EXDM, Operating Instruction

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9.9.7 Minimum speed cut off
Msco.
This function is primarily signi  cant for installation of the device as a pure P
Controller in refrigeration and air-conditioning technology.
For operation mode speed controller
1.01 without function!
Msco = OFF (factory setting)
If no “ Min. speed ” is adjusted, the fan stops with
reaching the desired value.
If “ Min. speed ” is adjusted (e.g. 20%), then no
disconnection of the fan takes place. I.e., al-
ways a minimum ventilation is ensured (fan
does not go under setting “ Min. speed ” ).
Msco. e.g. -2.0 K
It takes place a disconnection from setting “ Min.
speed ” to “ 0 ” , if the given difference is reached
related to the desired value.
At a plus value (+) before reaching the desired
value
At a minus value (-) after falling below the de-
sired value.
nM
50 %
100 %
I
Min.
Min. 35 % Max. = 100 %
20 °C
S
7 K
R
27 °C
-2.0 K
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v_min_luft_abschalt.vsd
Minimum speed cut off (idealized principle diagram)
nM Motor speed
S Setpoint
R Pband
I Actual value
9.9.8 Second Group
Group 2 ON value
Second group “ indirectly controlled ” (picture A)
Analog output “ AnalogOut 1 ” in IO Setup function
|
5 A
|
= group control is
programmed. This output is employed as the default signal for a speed
controller. If the default signal or the regulation deviation exceeds the group 2
switch-on point, group 1 is reduced to “ n-min group 2 ” . Starting here, both
groups run parallel at maximum power.
Second group “ 100 % energized ” (picture B)
Relay output (K1 or K2) in IO Setup function
|
8 K
|
= group control is pro-
grammed. A contactor is triggered via this relay contact, which directly
switches the fans of the second group to mains voltage. If the default signal or
the regulation deviation exceeds the “ Group 2 ON value ” switch-on point, the
relay for the second group switches on and the speed of the  rst group is
lowered to an adjustable minimum value. After that, the speed of the  rst
group increases back up to maximum.
nmin at Group2
Controller
Master
N
Si/ Se
A
Controller
Slave
Si 0-10 V
N
0 .. 100 %
1
2
0 .. 100 %
Controller
Master
N
Si/ Se
B
C
ON / OFF
N
0 / 100 %
1
2
0 .. 100 %
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v_zweite_gruppe.vsd
N Line
Si Signal
Se Sensor
C Contactor
Operating Instruction Econtrol – model series EXDM Programming
L-BAL-E008-GB 0945 Index 005 Part.-No. 00156742-GB
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