Electromagnetic flowmeter M910
Operation manual
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QF value represents flowrate for frequency 1000 Hz and can be set independently to the nominal diameter of the
sensor. QF value can be changed after selecting modes “b”, “c” or “d”. Fixed frequency value can be changed after
selecting mode “m”. Following values are pre-set:
Frequency output standard factory setting:
Mode
„Positive flowrate“.
QF
flowrate corresponds to the required nominal flowrate Q
N
PF1
limit corresponds to the required nominal flowrate -Q
N
PF2
limit corresponds to the required nominal flowrate Q
N
H
hysteresis corresponds to the required nominal flowrate Q
N
/10
Parameters PF1, PF2 and H are common for frequency, impulse and status mode.
5.2.1.3
Impulse output (1.3 OUTPUT P)
Impulse output is formed by a galvanically isolated transistor NPN switch. Voltage drop on the switch is 1 V in the
made mode. Maximum switched voltage is 50 V. Maximum switched current should not exceed 100 mA. Positive
output is on terminal 6, negative output is on terminal 5 and 7 (internally connected). Width of the impulse can be
set. Maximum frequency of impulse output is limited by the impulse width. For the shortest impulse 10 ms is
maximal frequency 50 Hz.
Impulse output can be programmed in one of the following modes:
a)
Off
output is not active (off state).
b)
Pos.Flow
1 impulse is generated when total volume QP of liquid has flowed in a positive
direction.
c)
Neg.Flow
1 impulse is generated when total volume QP of liquid has flowed in a negative
direction.
d)
Abs.Flow
1 impulse is generated when total volume QP of liquid has flowed in a negative
or positive direction.
e)
On Pos
output is off in case of negative flow and made in case of positive flow.
f)
On Neg
output is off in case of positive flow and made in case of negative flow.
g)
On In
output is on, when flowrate is higher than PF1 and lower than PF2, otherwise it
is off.
h)
On Out
output is off, when flowrate is higher than PF1 and lower than PF2, otherwise it
is on.
i)
Dose On
output is on, when programmed dose is counting, otherwise it is off.
j)
Dose Off
output is off, when programmed dose is counting, otherwise it is on.
k)
On>F1
output is on, when flowrate is higher than PF1, otherwise it is off.
l)
On<F1
output is on, when flowrate is lower than PF1, otherwise it is off.
If setting of flow limit is chosen, hysteresis H can be set too. Hysteresis is a tolerance field on one side of flow
limits PF1 and PF2. The output status changes (indicates crossing over pre-set limit), when the immediate flowrate
crosses over the value PF2 (or goes below limit PF1). The output status comes back to the default status, when the
immediate flowrate decreases under the value PF2-H (or increases over limit PF1+H) again.
Mode g ) with non-zero hysteresis:
Mode h) with non-zero hysteresis:
PF1 PF1+H
PF2-H PF2
OFF
ON
PF1 PF1+H
PF2-H PF2
OFF
ON