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Old 01-27-2023, 04:52 PM   #21
jasin1
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Quote:
Originally Posted by bobbecky View Post
Locked Rotor Amps or LRA, is the instant current draw at the moment that power is applied to the compressor and it hasn't started to spin yet, which gives you the maximum load you can expect on the circuit going to the air conditioner compressor. This is also stated as the inrush current that occurs on startup. This is also what the soft start devices reduce on these A/C units to keep the breaker from tripping by slowing the start of the compressor instead of just slamming it with full power.
yes but it’s only for milliseconds and most people wouldn’t have a meter to measure that (inrush current)……in the HVAC field ,LRA is a mechanically locked motor that you can verify by it pulling the listed LRA.

for example in one of the air cond units on the list that was posted earlier in the thread,if you take one of the small ac units rated at max 20 amp breaker, you will not see 63 amps at startup on a normally operating unit with a amp clamp…you will probably see a 18-20 amps for example..and then it will quickly settle down to around the RLA

not trying to argue but the topic of LRA is like the ford / chevy or auto propane valve open vs shut discussions
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