Figure 78: Rtd Wiring Diagram - ABB XSeriesG4 User Manual

If there is continuity, skip to step 7. If there is no continuity, verify that the wiring at the RTD head is correct.
If wiring at the connection head is correct, the RTD is defective. Replace the probe. Otherwise continue to the next step.
Check continuity of the second wire pair (typically white) by connecting one lead to each wire. The meter should read
zero or close to zero.
Check continuity of each wire (first pair either red or black as identified in step 4) to the probe or shield. If there is
continuity, the RTD is defective. Replace the probe. If there is no continuity, continue to the next step.
Check continuity of each second wire pair (white or as identified in step 7) to the probe or shield. If there is continuity, the
RTD is defective. Replace the probe. If there is no continuity, continue to the next step.
Check continuity of each first wire pair (as identified in step 4) to each second wire pair (as identified in step 7). The meter
should read approximately 100 to 140 Ohms. If this is the case, continue to next step. If not, the RTD is defective and
should be replaced.
If the probe is still not functioning correctly, re-check wiring using the supplied diagram (Figure 78). If no wiring error was
found, perform the RTD current source troubleshooting test in section 5.2.7, RTD current source (resistive) test.
RTD current source (resistive) test
If readings from the RTD are still suspect following the RTD probe continuity test, follow the instructions below to test the current
source on the termination board to verify it is receiving power.
Required equipment
–
Totalflow Diagnostics Kit 2017373
–
Digital multimeter with alligator clip leads
Step-by-step instructions
Begin by disconnecting power and communications from the XMV, if not already done.
Disconnect the RTD from the XMV, if not already done.
Set DMM to 200 mVdc.
Select the RTD test resistance value by selecting the resistor test connector from the FCU Diagnostic Kit, or make one
using a resistor appropriate for the unit:
–
Substitute the RTD probe wiring by connecting either a 100 Ohm or 123 Ohm resistor across connector terminals 3 and 4.
–
Connect a jumper wire between terminals 2 and 3.
A/I Jumper Settings
AI1 AI2 AI3 AI4 AI5
J21 J22 J24 J25 J26
Settings
1 2 3
(2-3): 0-10V
(1-2): 0-20mA
J21 J22 J24 J25 J26
AI 5 COM
AI 5 (+)
AI 4 COM
AI 4 (+)
AI 3 COM
AI 3 (+)
AI 2 COM
AI 2 (+)
AI 1 COM
AI 1 (+)

Figure 78: RTD wiring diagram

86
J20 AuxPwr Output
1 VBAT
2 GND
3 SW VBAT
4 GND
RTD
Signal Input wire from RTD