42
FMT230, FMT250
THERMAL MASS FLOWMETER | CI/FMT230/250-EN REV. B
… 7 Electrical connections
… Electrical data for inputs and outputs
Digital output 41 / 42, 51 / 52
Can be configured via Modbus.
A
Passive digital output 41 / 42 as pulse or frequency output, Passive
digital output 51 / 52 as pulse output
B
Passive digital output 51 / 52 as binary output
Figure 30: Passive digital outputs (I = internal, E = external)
Pulse / frequency output (passive)
Terminals
41 / 42 (pulse / frequency output)
51 / 52 (pulse output)
Output ‘closed’
0 V
≤
U
CEL
≤
3 V
For f < 2.5 kHz: 2 mA < I
CEL
< 30 mA
For f > 2.5 kHz: 10 mA < I
CEL
< 30 mA
Output ‘open’
16 V
≤
U
CEH
≤
30 V DC
0 mA
≤
I
CEH
≤
0.2 mA
f
max
10.5 kHz
Pulse width
0.1 to 2000 ms
Binary output (passive)
Terminals
41 / 42, 51 / 52
Output ‘closed’
0 V
≤
U
CEL
≤
3 V
2 mA
≤
I
CEL
≤
30 mA
Output ‘open’
16 V
≤
U
CEH
≤
30 V DC
0 mA
≤
I
CEH
≤
0.2 mA
Switching function
Configurable
Note
• Digital output 51 / 52
cannot
be configured as a frequency
output.
• Terminals 42 / 52 have the same potential. Digital outputs
41 / 42 and 51 / 52 are not electrically isolated from each
other.
• If you are using a mechanical counter, we recommend setting
a pulse width of ≥
30 ms and a maximum frequency of
f
max
≤
3 kHz.
