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Thermo Fisher Scientific

Interlock Board, K1 relay, 5V PSU


IPB Interlocks LEDs are green (2), but not Interlock all (3)


Titan Series


These are possible resolutions for the issue:

  • Adjust 5V PSU


These are possible causes for the issue:

  • 5V PS slightly below K1 relay threshold (5-15V)


The relay K1 is an electromechanical one and it has switch-on voltage of 5V and hold voltage of 3.75V on the IPB board (Interlock Patch BRD = General interlocks). Based on a recent onsite long and costly troubleshooting, we would propose to change the K1 relay specifications to match the 3-9V range (see blue circle in the tableau enclosed) rather than the currently used one 5-15V range (see red circle int he tableau). The price of such K1 relay is less than 2 euros but will save us long and costly Troubleshooting actions. Detailed Troubleshooting onsite with several boards swap prior finding the root-cause. After water stop-start all interlocks LEDs are green including (2), but not (3) - Interlock all (see enclosed scheme). FSE exchanged IPB - the same. Measured voltage on X4 plug on IPB shows 4.99V. After adjusting the 5V PS output to slightly higher then 5V and the measured voltage on X4 also slightly higher then 5V (in this case 5.08) fixed the issue.





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