Re: SM Climma AC - Calpeda Pump Voltage with Breakers Off
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Hi Dan et al,
Anyone who works on 240 volt circuits without turning of the power at the mains switch is living dangerously.(temporally) These currents are lethal. Likewise I wouldn't work on them with the gen set running
On 28 April 2019 at 02:14 Dan Carlson <carlsdan61@...> wrote:
I am on BeBe at Red Frog Marina in Panama wit 60Hz shore power. I just checked, with all the AC breakers off but the main GFI on, and I have: 1) 120v from blue to yellow/green, as well as from brown to the yellow/green. 2) I show 0 volts AC accross the blue to brown contacts (I don't understand how you could measure 240 v across the Blue to brown when the motor is not running?). 3) when I turn of the main GFI breaker there is no voltage. I did not test the generator.
That is a shocking discovery! It would be very interesting to get confirmation of the voltages from a boat on 50 Hz supply.
One thought: Could the stray voltage be coming back from the capacitor. It shows 0 across the Blue to brow because the voltage on the blue and brown are on the same cycle when there is only one 120v source? To test this I disconnected the blue and brown wires and measured the voltage of these independently: Blue wire to yellow/green was 120v, Brown wire to yellow/green showed 39v (Stray voltage?). The voltage across the Blue to Brown was 120v.
I'm surprised this has not come up before, as it creates a very unsafe condition for one assuming the circuit is de-energized. My conclusion is to disconnect at the pedistal when working on the AC circuits to be safe.
Daniel Carlson on sv BeBe, SM#387
On Fri, Apr 19, 2019, 9:37 PM Gary Silver via Groups.Io <garysilver= email@example.com
[Edited Message Follows]Hi Bill and Eric:
Yes, all the 220 panel CBs are double pole (both Line [brown] and Neutral [Blue] are switched). With all breakers open (tripped) there is still 240 VAC across the blue and brown leads at the Calpeda Pump when hooked to shore power, but not when the genset is running. Looking at the Climma schematic (really more of a diagram) the neutral and safety ground wires are wire straight thru from the "separate source" and the Line [brown] from the separate source is switched by the relays to provide line voltage to the pump when a given unit is switched on. So I can see perhaps that there might be 110 voltage between the blue and safety ground at the pump from this "seperate source" but not the 220 that I am seeing. Olivier, are you there? What is the separate source for the Climma relay box?
I believe that the "other source" supply for the relay box is directly wired from the 220 volt buss just down-stream from the GFCI 30 amp breaker on the side of the 220 volt panel before it is distributed to any of the CBs (Diruptors). The difference between Euro power and US power is noted and somehow plays into this. Will continue to puzzle this out along with you. Perhaps I need to get to sail to some European power, plug in and see if the mystery voltage goes away.
Thanks for your thoughts.
Gary S. Silver
Amel SM 2000 # 335
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