New Converter

As says in the OP, Randy has not got his listed yet. To see what it is go to the PowerMax website and find the PMBC or whatever the letters are and go to the PDF blurb for it. It mentions somewhere that the variable voltage is an option.

Without that option it acts like a regular PowerMax unit for its stages. However they do show it has different voltages--14.8vs Randy's 14.6 ISTR. Whatever. They all used to be 14.4 but that was then.

A Carmanah tech here in town told me their Go-Power version would not be getting that variable voltage feature. They switched converters from Iota to PowerMax a couple years ago. He said they are re-writing their manuals to correct some errors left over from when they had Iotas, especially the part about having the IQ4 gizmo, which PowerMax doesn't use of course.

I gather Randy has a shop at his place where he does his own version of the regular PowerMax so that is why you get the "Boondocker" name he invented and some other specs like 14.6 instead of the old 14.4, etc. So now it seems from the OP he will be soon coming out with his version of the Pwhatsit that does have the variable voltage. I hope it also has the little voltmeter on top like my prototype does but if it doesn't, you can just clip your meter's leads to the unit's terminals and read your meter while you twiddle the knob.

BFL, here is the link to the PowerMax PM4B-60 at Best Converter. I recall when you were doing that beta testing, but there is no mention on the Best Converter site about any PowerMax Boondocker model with variable voltage output control, unless I am missing it. Possible that PowerMax is making it and Randy isn't carrying it?

What can I say.. I like my totally automatic with manual override Progressive Dynamics 9180 with Wizard.

I also have some smaller ones. including one I designed and built, and it is ,,, completely manual adjustable like the one you describe. It was designed to be the power supply for the radio that is in my car, when said radio was NOT in the car... And it works well.

Very interesting. I don't have enough internet access right now to search and link, but maybe somebody can find the thread I had on the 100amp prototype of this.

I would not call it a converter which might lead some to think it is a good choice to swap out their old one. You want an "automatic" for that role usually.

It is a specialty item derived from the car showroom unit PowerMax makes which is very popular in that world. It has model name starting with P I can't remember. Go-Power sells them too, but theirs does not have the variable voltage feature and they chose not to get that for theirs. Glad to see Randy is going ahead with this; he must now figure there is a market for that variable voltage feature.

Also there is a long thread from last winter on how I had trouble with the input thermistor blowing when I did not follow proper procedure for using the unit at start-up. I hope Randy makes mention of this procedure in his owner's manual for it. Go-Power mentions to connect first then start, but does not highlight that enough IMO.

The company may have resolved that thermistor issue since then, don't know. They were looking at a design fix for the 100amper which has a very high inrush if you set the voltage high. It works great as is if you follow procedure, so don't worry.

In any case, the main lesson is NO hot restarts, and DO clamp on first before starting it --the reverse acts like a hot restart. You only want to start it with a cold thermistor and it takes quite a while to cool down it seems--I would wait at least a half hour. Technically it should only take a few minutes but it takes longer!

Not clear what the OP wants his for, but note that the other PowerMax units have the 60 amper not power-factor corrected, while the 75s and up are. This means you can run them on a 15a (AC) circuit instead of a 20a circuit. Also that your 75 will not draw any more from your generator than the 60 would.

One of my recommendations on the prototype was to mark the top around the voltage knob with some voltages at no-load not connected to battery. Once you connect to the battery, the voltage meter reads something else nearer the battery voltage, so you cannot set the unit's own voltage accurately. With a little scale around the knob, you can set the voltage to the 15v marker when the meter is showing say 13.9, and now you can be sure it will bring the batts from 13.9 to 15 and hold there. If you don't have that marking, you have to wait till the batts get to 15 and then twiddle the knob so the meter says 15 and then it will hold there. (If they do have a scale on them now, I would do a confirmation check on it in case it is a little off "calibration" where there is a little "play" in the knob or whatever. You can then note any index error on the scale for future use)

Let us know how it works out. Maybe a test thread? :)

Bestconverter.com I have a secondary app for it so got one. They are waiting on labels but I don't care about that.

Where did you get it from?