Owner's manual
HMP228
Operating Manual M210282en-A
10
when the probe is pulled
out for maintenance, cap
the hole with a capped nut;
this way, the process can
be open although the probe
is not in place
capped nut
DIN 917-M22x1.5
sealing
closing valve
(ball valve)
welded sleeve
(G1/2) or tube
with thick walls
probe
Figure 2.2.4 Installing the sensor head directly in a process pipe
2.3 Signal cabling and grounding
2.3.1 Electrical connections
CH1- and CH2- are connected
together internally (X2).
DO NOT USE POWER SUPPLY
GROUND (-) AS OUTPUT
SIGNAL GROUND (X1)!
24V
Sensor connections
Current loop or
RS485 module
Ch1
Ch2
+
-
nc
Tx
GND
Rx
--
+
+
X1
X2
+ Ch1 -
+ Ch2 -
+ 24V -
Power supply
V
mA
V
mA
Figure 2.3.1 Electrical connections