The Case of the Lazy Washing Machine

THE MYSTERY

A corrections facility in the area called ACES because one of their industrial washing machines (100 lb. capacity) was down. They called an electrician in to look at it, but he was unable to find the problem.

THE CLUES

ACES sent a Control Scene Investigator to the site, and he immediately noticed that the washing machine was equipped with a Variable Frequency Drive. VFDs can sometimes cause the symptoms exhibited by the machine, but the CSI decided to first examine the power supply.

The machine was powered with a 210 volt 3-phase line, which is 3 wires that should have 210 volts on each leg. Just as the CSI was testing the line with a multimeter one of the wires went out, resulting in partial power, or a brownout. This can be a tricky situation because it appears as though something’s wrong with the machine — the controller can still function on only two legs, but the machine itself needs all three legs to turn over.

THE PERP

After tracing the power line all the way back to the breaker box, the CSI determined that the circuit breaker didn’t have power on the dead leg.

THE SOLUTION

The breaker was old and obsolete, and replacement parts were no longer available. The CSI wanted to avoid having to replace the entire panel, so he resorted to a time-honored and highly technical procedure known as “exercising the breaker”. This consists of vigorously flipping the switch back and forth many times to knock loose internal corrosion.

After completing this intricate maneuver, the washing machine fired right up and continues to run perfectly, without requiring the customer to make costly upgrades on short notice.

This is a rare case where the first line of investigation proved to be the culprit, and the problem was easily solved. Whether simple or complex, ACES CSIs are specially trained to isolate and resolve most any troubleshooting situation.

CASE CLOSED