Which of the following is the probable cause...

Which of the following is the probable cause...

Question 1 of 270705eccef9bbacbc34ba4d455e8

Which of the following is the probable cause for a motor driven, low pressure, reciprocating air compressor to repeatedly trip the circuit breaker upon starting?

Question 1 of 27070

Q

Which of the following is the probable cause for a motor driven, low pressure, reciprocating air compressor to repeatedly trip the circuit breaker upon starting?

🔍 Key Concepts

• Starting current and load on electric motors – what happens to current draw if the compressor starts under heavy load vs. no load • Unloader system on reciprocating air compressors – what it is supposed to do during startup • Difference between a pressure switch problem and a mechanical loading problem

💭 Think About

• Ask yourself: At the exact moment of starting, which condition would make the motor draw the HIGHEST current and trip the breaker? • What is the unloader’s job during startup, and what happens to motor load if it does not do that job? • Which choice would actually REDUCE load on startup, and therefore is unlikely to trip a breaker from high current?

✅ Before You Answer

• Identify which option would cause the compressor to start under maximum pressure/load already in the cylinders or discharge line • Check which options would tend to lighten the load (and therefore be less likely to trip the breaker) rather than increase it • Confirm that the most probable cause is the one that makes the motor work hardest at the instant of starting, causing overcurrent