Sandeep Bishla

FAQ / Troubleshooting of Causes of Stress

In an Electrical Switchboards there are multiple types of problem may occurs but few of them are comes in frequent manner so by taking immediate action we can resolve or analysis the problem to encounter. Whenever we are going to do below activities we must know experience technician is required to perform below steps:-

S. No.ProblemCauseSteps for Troubleshooting
1No Indication-No Power-No Control SupplyCheck the Supply at I/C Feedera.  Check control supply terminals for presence of voltage as per drawingb.  Check auxiliary supply to measuring instrumentsc.       If control supply available as specified in the drawings then check MCB for proper operation
2No Measurement-No Power-No Control SupplyCheck the below at I/C Feedera. Check control supply terminals for presence of voltage as per drawingb. Check auxiliary supply to measuring instrumentsc. If control supply available as specified in the drawings then check MCB for proper operation
3Power monitors not showing any readings-Auxiliary supply failed-Voltage & current signal to instrument not availableCheck wither auxiliary supply to meter is present :-a. Check voltage at terminals of meter as per drawingb. Check CT terminals for removal or shorting
4Circuit breaker not closing automatically or manually-Closing circuit not healthy-Tripping circuit operatedFirstly check auto/manual selector switch for desired positionAutomodea. Check trip indication of all Protective Relays.b. Check electrical interlocking circuit as per drawing.Manuala. Check supply to closing coil.b. Check whether breaker spring is charged or not.
5Breaker closes but tripsFault in power circuitCheck flags/ indication on protection relay, reset and close the breaker if problem persists check distribution circuit for faults.a. Check supply to U/V coil.b. Check whether Under Voltage Relay operated.
6Power monitor not showing proper readings-Current/ Voltage signals not proper-Program of power monitor may be erratica. Check Current and Voltage signalb. Program of the power monitor for voltage signal and CT ratio check and reprogram as described in the operations manual.
7CT Meters not showing readingCT shorting terminal mat be shorta. Open all shorting terminal provided in metering compartmentb. Check whether load is available or not

To encounter many issue related to above listed problems, a small amount of maintenance provides huge gains in reliability. Some basic things that need to be in the preventive maintenance procedures include:

  • Pest control

This may consist of a rodent trap in one corner. Whatever method, ensure it’s inspected periodically.

  • Dust control

Vacuum the accumulated dust off the cabinet floors. If conditions require vacuuming anything else, remember it’s an energized cabinet — follow the applicable procedures. Don’t vacuum near circuit boards without following electrostatic discharge (ESD) rules.

  • Connection control

It seems counterintuitive, but re-tightening terminal screws causes loose connections. Instead of inadvertently over-tightening terminal screws (consequently diminishing their clamping power), use an infrared gun to see which terminals are high resistance. Disassemble, clean, and reassemble.

  • Insulation

An insulation resistance testing program is the best way to prevent wiring failures.

By taking a few extra steps in the selection, design, and installation of an industrial control panel, you can ensure it will have no failure time bombs ticking away. With a modest maintenance program, it will be nearly problem-free for its entire life.

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top