MAXICAL
®
III
5511-229 GB/98.06/Rev. B1
18
4.5 Flow Meter Input (75-76)
This flow meter input is galvanically separated via an optocoupler
and designed for electronic flow meters with active frequency
output of max. 5 kHz or 10 kHz. The flow meter’s frequency
output must have an amplitude of 12...30V. Pulse duration must be
at least 30
m
sec.
The flow meter connected must use MAXICAL
®
III’s pulse
separation (CCC
³
300) and preprogrammed Qmax. The internal
flow switch must be set at 75-76 - please refer to chapter 4.6.
If the CCC code lies between 300 and 303, the frequency output
from the flow meter must be 5 kHz at Qmax.
Max. cable length should not exceed 50m.
4.5.1 Flow Meter Connection
MAXICAL
®
III connects with almost all flow meters with active
pulse output. Below please find various examples of electrical
connection.
Please note that the flow meters must be configured correctly as
far as Q
max.
and f
max.
are concerned, and that some types of meters
are to be specially ordered for active output.
