I did. So I had some fun.
This is an ancient baby Waeco. 18qts I think. Compressor.
LHS is zero current. Every grid interval vertically is 20mV or 2.7A (I'm using an in-line shunt between the battery and the fridge input connector). RHS is the fridge humming away at a bit over 3A. Each horizontal interval is 100ms.
So, looks to me like it starts (I can hear a relay) and for 0.2s it takes in about 3A fairly smoothly getting ready, then the compressor starts, sucks in up to about 11A for about 0.1s, and then settles down at 3A. All that not including the significant extra noise.
IOW, the startup peak current is over 3x the steady-state one. No big surprise, of course, but fun to see first-hand:
and then, looking at the pulsing on the RHS, and counting them, I get about 2,700 / min, presumably the rotation speed of the motor or some multiple thereof.
This is an ancient baby Waeco. 18qts I think. Compressor.
LHS is zero current. Every grid interval vertically is 20mV or 2.7A (I'm using an in-line shunt between the battery and the fridge input connector). RHS is the fridge humming away at a bit over 3A. Each horizontal interval is 100ms.
So, looks to me like it starts (I can hear a relay) and for 0.2s it takes in about 3A fairly smoothly getting ready, then the compressor starts, sucks in up to about 11A for about 0.1s, and then settles down at 3A. All that not including the significant extra noise.
IOW, the startup peak current is over 3x the steady-state one. No big surprise, of course, but fun to see first-hand:
and then, looking at the pulsing on the RHS, and counting them, I get about 2,700 / min, presumably the rotation speed of the motor or some multiple thereof.