em-tec BioProTT - Passive Wiring: Powering via Current Loop

BioProTT
TM
Flow Measurement System Version 1.00 page 20 of 75
6.1.2 Wiring in “Passive” Set-Up when Powering Flow Meter via
Current Loop
In a passive set-up, the current loop provides its own power as per definition. The power
from the current loop is then also used to operate the flow meter.
Since the flow meter always needs power to operate, you need to apply a logical “jumper”
to use the power from the current loop and provide it to the flow meter. This is explained
in detail below.
Figure 7: BioProTT flow meter rear view with one analogue plug connected -example w/ RSS socket
Pin No
Flow / RSS
Wire color
(in supplied cabling)
Connected with
1
24 V (24C_in)
Brown
Connect Pin 1 with Pin 2
Note: due to the wire bridge,
the flow meter is now powered
also!
2
Current Loop +
White
[see above]
3
Ground in
(GND_in)
Blue
Ground (GND) / Return of
PCS
4
Current Loop -
Black
Send (+) of PCS
Figure 8: Schematics - looking at pins of rear of flow meter of either Flow or RSS socket
Please note: only supply power to the flow meter via one of the sockets to avoid any
potential electrical problems. Either Flow or RSS socket pins can be used, when
power is supplied from the loop.
3
4
2
1
PIN 1: +24 V
PIN 3: Ground (GND)
PIN 4: Current Loop (-)
PIN 2: Current Loop (+)
Return (-) Send (+)
of PCS