Aquametro Oil & Marine CONTOIL VZF II, Монтаж и эксплуатация

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Analog current loop
(4...20mA)
Setup menu: Analog current loop
mA
4.0
20.0 I
20
I
4
Q
2
/ T
2
Q
1
/ T
1
I
4
: current 4mA
I
20
: current 20mA
Q
1
: chosen min. flow rate
T
1
: chosen min. temperature
Q
2
: chosen max. flow rate
T
2
: chosen max. temperature
The current signal is proportional to the flow rate or
temperature range of Q1/T1 to Q2/T2
Signal behavior:
when a relevant flow meter error occurs:
Value falls below the set lower flow rate / temperature
value Q1/T1:
proportional decrease to 3.8mA which is then
maintained.
Value exceeds the set upper flow rate / temperature
value Q2/T2:
proportional increase to 20.8mA which is then
maintained.
(continuing output of actual value 3.8 … 20.8 mA).
Error signal for measurement relevant error (sensor,
ROM, supply voltage, etc.)
For HIGH error behavior: output 21.5 mA
For LOW error behavior: output 3.5 mA
For ACT error behavior: no error signal,
Damping of the signal [tAU]
for rapidly changing values.
Note: The higher the time constant, the more sluggish the
signal.
This parameter is used to avoid “jumps” of the signal .
Parameters that can be set:
Lower value
[MIN]
: Q1/T1 ≥0 (factory setting: Qmin / 0 °C)
Lower current
[mA]
: I
4
= 4 mA
Upper value
[MAX]
: Q2/T2 ≤ Q/Tmax (factory setting: Qcont / 100 °C)
Upper current
[mA]
: I
20
= 20 mA
Error
[Err]
(factory setting: Err Act)
Notice:
Qmin
,
Qcont
and
Qmax
are dependent on the nominal size of the flow meter.
[tAU]
Damping value (Tau)
1 (no damping) … 9 (max. damping) (factory setting: 4)
Example:
Q
1
is 50 l/h and Q
2
is 500 l/h
By 50 l/h a signal of 4 mA is being sent
By 275 l/h a signal of 12 mA is being sent
By 500 l/h a signal of 20 mA is being sent
the flow range of 450 l/h, will be distributed across the range of 16 mA (20 mA
– 4 mA).