My Inverter/Charger Seems to Cycle On and Off

[montenido]

Hi all,
I have a Xantrex 3000 watt inverter/charger on my boat. My shore power runs through this setup and keeps things charged while providing AC power. When I am on batteries alone and turn on the inverter, it seems to "cycle" and search for a load. As an example, last week in inverter mode, my electric drill would not work until the inverter supplied its periodic power, maybe every 20-30 seconds. Once captured, the power would remain on as long as my drill was being engaged. Once I released the drill trigger, power would start to cycle on and off again, again at 20-30 second intervals. This is the first inverter that I have owned, so I am not real familiar with their operating characteristics. It was already installed when I bought the boat.
Does this sound normal? If not, can anybody offer any suggestions on what checks I might make for troubleshooting this?

Thanks, Bill

[transmitterdan]

This behavior is probably normal. I have a Mastervolt that does something similar. You should read the manual with your inverter and see if it has different options for saving power. Many inverters have different modes like this:

1) Full AC output all the time
2) Low AC output until the current increases and then full voltage
3) No AC voltage except for brief periods where it checks if power is needed then full AC voltage until current goes back to zero.

It sounds like you have yours set for something like #3. All the inverters I have seen can be set for #1 but that mode uses considerable battery power even though there is no AC load. But you may want to leave yours as it is because this saves quite a lot of battery power during periods of inactivity.

Good luck,
Dan

[Andina Marie]

I would just flip on a cabin light to provide enough load to keep it running when using light loads that failed to kick it in. Mine did not have your periodic test start, it just put out a low voltage that frequently was too low to trigger electronic controls in loads like a drill trigger.

[Le Tour]

This does not sound correct. I have the Xantrex SW 30 (3KW inverter-150amp charger) and it does not behave that way. It provides seamless AC power on demand. In the past 17 years I have owned two other Xantrex and Heart Interface inverters. I have used numerous power tools, coffee pots, microwave ovens, stereo amplifiers etc. and have never observed that behavior. There is a setting for the "idle threshold" but you need the System Control Panel to set that threshold. It sounds like it might be set too low. One of the other readers had a clever suggestion of turning on an AC light or other load. If that solves your problem than I would guess the idle threshold is too low.

[FlyingCloud1937]

Originally Posted by Andina Marie

I would just flip on a cabin light to provide enough load to keep it running when using light loads that failed to kick it in. Mine did not have your periodic test start, it just put out a low voltage that frequently was too low to trigger electronic controls in loads like a drill trigger.

or just set the search watt feature

Someone above mentioned that this was/is an energy saving feature.....it is

And as Andina said below just wire a toggle to something above the set current, if you want everything to be on all the time, that way when you go to bed, you know the refer, and the frezzer will run all night when demand requires.

Lloyd

[Paul Elliott]

My Xantrex does the same thing, although the cycle-time is only about five seconds. This is definitely a power-saving feature.

[deckofficer]

Even my 25 year old Trace 2012 does this in search mode, but as Paul said about once every 5 seconds looking for a load. Funny thing, that short little power up looking for loads was enough to keep my VCR clock keeping time. If memory serves, if I set the threshold so low a wall cube for charging would keep it on, then for 24 hours per day I would be wasting about 300 w-hr for the inverter to always be on. If left in search mode with a higher threshold it would be 1/10 the drain.

I had to use dip switches to set my parameters for search threshold, voltage and current for charging, and a few other things looking at the instruction sheet. I hope the new inverters have a better user interface like a screen menu and function switches.

Welcome to the world of inverters and power saving of your stored electrons.

[Le Tour]

Correction, the idle threshold is set too high or malfunctioning. Once a load is applied the load sense circuit should power up the inverter and maintain power. A several hundred watt load like a drill motor should easily trip the load sense circuit to maintain AC inverter power. It is evident that others are seeing the same behavior, but ... if the unit parameters are configured properly and the load sense circuit is operating as designed, I don't think you should see the behavior you have described.

FWIW, I had a charging issue with my Xantrex where it would not consistently move into the Float phase of charging. This is a potentially harmful due to over charging. The solution was to set the parameters specifically for my battery bank configuration. The standard factory settings were close but not close enough. Unfortunately, the only way to set the parameters was to purchase the System Control Panel (SCP) for $170 bucks. The Xantrex unit does not allow the user to change settings without the SCP. I was not too thrilled about the extra "hidden" cost. However, once the unit was configured properly it behaved as advertised. No more charging issues. Good luck.