Off grid solar chest freezer to fridge conversion complete

[ExtremeX]

Originally Posted by GUNNTZ

What would be another option? I personally haven't seen another brand that protects against output issues like a brownout. Wouldn't you trip an over current or over load before these inverters brown out or are you addressing equipment start up related problems?

...you would expect at least that right? That's why I said "kinda junky".

Any quality pure sine option is going to cost a crap load more money... Personally I am moving away from 12v inverters... they start getting a lot nicer & better value when looking at 24v and 48v models.

All I was trying to say is that its a clear case of you get what you pay for here. Their clearance prices were certainly bottom dollar, but for the money paid, not half bad.

My biggest grip is that that there are no protections at all... you as the user must know what type of loads you are dealing with, what type of start up currents you have, and have some way of monitoring it yourself because that inverter isn't going to do it for you...

That said, mine does work within its rated wattage... but if you ask more, you just get a constant brown output.

Here is something near a 600 watt load... output measurement (554 watts)


Here the DC side of that load...


Here is what happens when you ask more from the inverter, which is still under its "startup / max" 1200 watt rating...

It doesn't shut off output, no alarm, its still moving like 5 amps of current, but just sags the AC voltage like crazy @69V.

I don't have an oscilloscope... so I can't comment on the quality of the sine wave, but I would suspect "good enough" when under 600 watts, but id love to see what it looks like in a brown output condition haha.

[GUNNTZ]

Originally Posted by ExtremeX

...you would expect at least that right? That's why I said "kinda junky".

Any quality pure sine option is going to cost a crap load more money... Personally I am moving away from 12v inverters... they start getting a lot nicer & better value when looking at 24v and 48v models.

All I was trying to say is that its a clear case of you get what you pay for here. Their clearance prices were certainly bottom dollar, but for the money paid, not half bad.

My biggest grip is that that there are no protections at all... you as the user must know what type of loads you are dealing with, what type of start up currents you have, and have some way of monitoring it yourself because that inverter isn't going to do it for you...

That said, mine does work within its rated wattage... but if you ask more, you just get a constant brown output.

Here is something near a 600 watt load... output measurement (554 watts)


Here the DC side of that load...


Here is what happens when you ask more from the inverter, which is still under its "startup / max" 1200 watt rating...

It doesn't shut off output, no alarm, its still moving like 5 amps of current, but just sags the AC voltage like crazy @69V.

I don't have an oscilloscope... so I can't comment on the quality of the sine wave, but I would suspect "good enough" when under 600 watts, but id love to see what it looks like in a brown output condition haha.

Thanks for providing the extra info on them. I guess it's what in kind of expected at near max start up draw. Is that voltage drop sustained or momentary? What size of cable was connected to the battery and how many amp hours deliver? Not doubting your findings, just trying to see if there are variables effecting the output. I'm definitely not defending Zamp, just trying to figure out if it's even worth keeping my 1k for my next project. Just a little FYI, even commercial or residential loads you'll see a drop on equipment the has high starting load(also effected by wire gauge going to the load), but not that drastic. Again, thanks for the info and heads up.

[ExtremeX]

Well aware of start up current, voltage drop, and all that good stuff... I am using a short run of 10 AWG directly to the 12v batter of a running truck.

The load was a persistent high load... above the RMS rating of the unit, so the drop voltage drop was sustained.

The point of the demonstration was to test overload protection... which is an advertised feature that does not work... nothing more or less.

The unit does not shut off, alarm, or manage the overload condition... instead, it passes bad power directly to the load.