IM-P330-74
MI Issue 1
2
Please note: This document must be read in conjunction with IM-P330-73
Caution
– The Flowin end of all shielded cables must be grounded to the earth points provided,
as described in Section 3 of the Information and Maintenance Instructions (IM-P330-73),
otherwise the EMC performance of the Flowin 2 will be impaired, possibly resulting in flowmeter
damage or loss of accuracy.
The Flowin 2 must be earthed to the installation pipework, using the braided cables, shake-
proof washers, and the hexagon screws supplied.
Recommended specification of loop power supply and pulse output cables
The loop power supply and pulse output cables must be: 7-strand, screened, twisted pair
with a cross sectional area of 0.5 mm
2
. The screen must be earthed at the Flowin end of the
cable only. The maximum cable length must not be greater than 300 m, but in practice is
governed by the number of loop devices, cable capacitance and total network resistance.
EIA 232 (RS232)
Communication port
(RJ11 socket)
Remote NPN input
(maximum 28 V)
Fig. 2
Remote PNP input
(maximum 28 V)
OR
Loop
powered
4 – 20 mA
display unit
or chart
recorder
9 - 28 Vdc
+
-
R
R
230 V
50 Hz
+
-
1
2
3
4
5
Power
0 Volts
Fuse
1 A
Power
0 Volts
R
10 K
OR
M750 display
unit
with
4 - 20 mA active
input (supplying
current loop)
N
L
Pulse
Loop
+ -
+
-