Liquid Controls T650N SERIES - Manual (Page 13)

Sponsler, Inc. T650N Series Cryogenic Truck Totalizer pg 13 DOC# MN-650
SYSTEM TROUBLESHOOTING
Procedures:
When a failure is believed to exist, the following procedure will aid in expediting the isolation of the failure.
1. Check all wiring for secure and accurate connections. Ref. DRAWING # T650NIR-1
2. Check that sensitivity (R1) setting is mid-range (11 o’clock), and depress S9. Observe all LED’s
and the displays.
3. Follow the troubleshooting diagram (next page) for the following:
SYMPTOM
No Display
Display “ON” – No Count
Display Counts – No Accumulative Count
This test is designed to troubleshoot the 820 Temperature Compensator after the 650D and 650F Boards have
been proved functional (unit functions correctly when S12 is in W/O TC position).
Refer to Drawings:
SCI-820-CONN-VOL-9-01
T650NIR-1
Troubleshooting Diagram
Preliminary Checks:
1.
Probe Cable: Check continuity between Pin A and WHT wire; Pin B and BLK wire.
Check NO SHORT between Pin A and Pin B or between Pin A or Pin B and the
connector.
Insure that the probe cable wires are securely attached at J1-11 and J1-12.
2.
Probe: Check resistance between Pin A and Pin B
If the RTD is at ambient temperature, resistance range 100 to 110
If the RTD is immersed in liquid product at delivery temperature:
LOX resistance range 18 to 42
LIN resistance range 16 to 37
LAR resistance range 23 to 42
CO
2
resistance range 84 to 96
If the resistance reading is NOT within the specified range, replace the RTD
3.
Insure that interconnect wiring harness is installed properly and securely at 650F J2-A and 820 J2 and
J4.
4.
Insure that the 820 Product Selector Switch (SO) is in proper position for product being measured.
5.
Check placement of jumper on 820 PCB. Ref DRAWING # SCI-820-CONN-VOL-9-01. If installed at
‘B’, the unit will not count while the temperature is out of range for the selected product. The alarm LED
will be “ON” if the temperature is out of range.
6.
Set S12 in W/TC position. Turn Power “ON”. Display is “ON”; D11 is “ON”; D12 is “OFF” (Probe is
immersed in liquid product). Depress S9. If D3 and D4 don’t flash (unit does not count), proceed to
Troubleshooting Chart (next page).