Vaisala HMP230 - Manual (Page 75)

HMP230 SERIES
M210225en-B User's Guide
69
8.5. Measurement of output currents using test points
If a current output has been connected e.g. to a process computer, the output
current cannot be measured at the output connector X2 without disconnecting
the external load. The output current can, however, be measured at test points
CH1+/CH1- and CH2+/CH2- without disconnecting the output wires. These
test points can therefore be used in one point offset correction against an accu-
rate reference or in checking the current output without disconnecting the
analogue output from the process.
X2
OPENED COVER OF THE HMP230
X15
CH2
CH1 +
+
C
H
1
+
C
H
1
-
C
H
2
+
C
H
2
-
Figure 32 Location of the CH1 and CH2 test points
CH1+ CH1-
TEST POINTS
CH1+
CH1-
mA
R
L
X2
Figure 33 Circuit diagram of the analogue output current test points