Powermax 110 Volt to 12 Volt DC Power Supply Converter Charger for Rv Pm3-55 (55 Amp)

Before purchasing I read reviews, and some said this unit would not output the rated current. I have seen this 55amp unit output 45amps when my two group 31 batteries were at 12.5V with an additional 12V load of 16 amps. Also it switches between charging cycles as you would expect. But FYI, I have a Honda EU1000i generator and it cannot start this charger if the battery voltage is below 13.4V. So I needed to use a 10 amp charger, bring the batteries up to 13.4, and then switch over to this charger. I called the manufacture to ask if there was any way to limit the maximum current. And they answered the phone! There is no way to adjust it. You can adjust the voltage levels but this would not be enough or the correct way to fix this. They told me for my Honda eu1000i I would need to go to the 35 amp model. The fan is noisy and only runs at one high speed.

I couldnt be any happier with this purchase! Great quality American made product at a reasonable price. Does exactly what its supposed to do right out of the box. My 20 year old 45 amp converter went belly up, so I replaced it with this 55 amp unit. Unit was on my doorstep within 48 hours. Took about 30 minutes to install including time to drill a couple of new holes to accommodate the larger unit. House batteries were fully charged within 12 hours and system voltage has been floating at 13.1 ever since.

Installation was straight forward and product works as intended I’ll try and fallow up before the end of summer Works fine on my keystone raptor 3612 the old converter was not allowing batteries to charge from generator

I ordered this converter to replace the giant OEM converter that was sucking our house batteries dry in our 1986 Foretravel Grand Villa Barn Find restoration project. The install was straightforward and simple. I have watched the converter for about a week now and it is keeping the batteries very stable and functional. I have attached a picture to show the compartment that will be an Auxiliary electronics bay. Eventually this will mounted on an aluminum slide out tray for servicing or additional wiring. Although the old converter was a 75 Amp converter, I seriously doubt that the old converter would push the 75 amps, so in this instance, I opted for the 55 Amp model. Under full load, the Powermax is more that adequate. Also the fan noise is about 80 decibels less that the original. Its fan is temperature controlled and is not much more than a whisper when on. the old converter sounded like a box fan from the minute it went on shore power and ran constantly. My thought is: If you are looking to replace your old battery burning converter, look no farther. The Powermax converters are dependable, quiet and will do the job you need quite admirably.

Dont pay extra for faster shipping, it will not make it on that date. It came on the regular date if I had not payed more. Product is working great thou, install was easy.

Update Jan 29 2015, Sent back,. Told it was a mislabeled 15 amp unit. I would recommend others use a good clamp-on ammeter and see what they really got. I ended up buying an Arterra WF-9865 65 Amp DC Deck Mount Converter. Puts out 74 Amps, Fused for 80 Amps, linear reduction in charge until final trickle charge @ 2mA @ 13.25V. Just perfect. Matt Update Jan 8 2015, My 55 Amp unit still performs as if it is a unit rated for 19 amps. After talking with a very polite Service Engineer about this issue and given all the good ratings, I figured I owed an extra round of tests to verify my initial findings. This time using a different set of conditions. Instead of discharging the battery set @ 120 Amps down to 10.5V I reduced the discharge rate to 27 Amp/hrs until the battery source reached the same 10.5V. At this point the load was removed and this charger connected and recharge was started same as in the first tests. Of course, at that point the 230 Amp/Hr battery was in need for the 55 Amp charge rate. Unfortunately the charge rate was again, just 19.3 Amps. Bottom line is.... at this point I am very suspicious. The documentation shows operational mode curves without numbers which makes them curious but useless to me. The units 3 stage charge control intelligence logically transitions as expected but the units maximum output is still just 1/3 its claimed rating. Working with seller to resolve the issue. Matt Submitted Jan 2 2015 (by the guy that bench tests stuff before installing) * Unit is rated for 55 Amps but its maximum output will never exceed 19.3 Amps even while loaded down to 10.5 Vdc. No explanation can justify this as normal. Otherwise it controls excellent as the 3 stage chart indicates. I imagine this unit is mislabeled or defective. * I wish I understood why it came with a 30 Amp fuse. Documentation says its for Reverse Polarity Protection. Sounds like a good feature given this units output connectors are not labeled at all. Meter it and label it immediately if you get one. * If the unit is just defective and not just a overrated output claim I will very likely bump it up a notch and get a 75 Amp replacement but waiting to hear from the seller first. Judging by other readers I hope for a 5 star update soon. Matt

So far - Very quite and works perfectly for powering up the 5th wheel 12volt system. This unit is rated 10 amps higher than the one I removed that had burned up. My 5th Wheel has a battery disconnect switch and I am using this with the batteries completely disconnected. The only power is it having to supply at this point is the solenoid that connects the power distribution station to the rest of the trailer. This is because I am sure the batteries are old and have internal shorts. I cannot get them to take a charge at all. I dont want to spend 200.00 on another set of batteries that will just be sitting for the next 8 months. That is why I have the switch set to full disconnect from batteries. Considering the local camping supply outlet wanted 100 bucks more than this one (for a 55amp unit), I decided to test this unit out. I read the review about the actual output compared to the rated power output being only half of what the sticker states - but when I took out my old 45 amp unit, the sticker on the bottom that had the Quality Control testing specs hand written on it were approximately half of what the sticker said its max rated output was too. So I thought Ill give it a shot. My needs are not any where close to 45/55 amps for the purpose Im using it for. Hope this helps

UPDATE 12/26/19 I found good instruction on how to set this up. Disconnect the charger from the in coming AC supply. On one side of the charger there is access to a micro switch to set the charger onFIXED or 3 STAGE . Get a flashlight and a tweeker (small screw driver, philips is best, a very small straight slot will work). Set the micro switch to the fixed position. With the charger connected to the battery(s) and nothing drawing energy from the battery(s) (this is called no load) and the AC supply connected the the charger place your multi meter on Volts DC (VDC), read across the two output terminals. If the output voltage is not 14.4 VDC, there is an adjustment next to the Fixed / 3 Stage micro switch. Careful!! These adjusters are delicate and sensitive to pressure! Gently turn the adjuster counter clockwise, while monitoring the DC voltage on the output terminals of the charger. Once you have the voltage set to 14.4 VDC, disconnect the charger from the AC input power. Change the micro switch to the 3 Stage setting. Plug the charge back into the AC supply. Your charger should boost the battery(s) up to 14.4 VDC, then go into float mode. Mine works correctly now. All is happiness now! I have this connected to a bank of 3 deep cycle batteries. The charge stops at 13.2 volts. The information indicates the charger has Boost (normal charge pushes the battery up to 14.4 VDC) Float which like a trickle charge once the voltage reaches 14.4 VDC. Equalize ( forces the batteries up to 14.7 VDC to mix the acid and water and may desulfate also). This charger stops at 13.2 VDC. This is from the manual: ADJUST FIXED VOLTAGE DESCRIPTION: The unit is on the three stage charging mode firstly. From this statement I believe the charge is setup from the factory to provide the 3 stages of charging, I described above. Based on other customer comments I would not recommend this Converter.

Does what they say. Once you get it fine tuned in. I prefer using the middle setting on charging an battery an running auxiliaries. Ran on 1 an 3 the fan kicks on an then turns off. I’m not sure if it’s supposed to do so. But works great an doesn’t produce a lot of heat it stays fairly cool. I’ve put atleast 100+hours on it in the past month an it works properly! Good buy for the money

You loosen 3 screws on the old one and unplug it. Put the wires back just like you took them out and plug it in. DONE 10 mins. I was a bit surprised that the exact brand and part number that I replaced 2+ years ago had already died. Im giving the same brand another chance. Its says RV so open your wallet.