Advice on replacing my IOTA battery charger for boondocking

BFL13, just replied, thanks.

otrfun--sent you a PM

otrfun wrote:

BFL13 wrote:
My PowerMax converters (100a, 75a, 55a) have all met and exceeded their amp ratings (103, 76, 56). There are two main reasons for not reaching converter rating:

1. Using #8 output wiring. Needs #4. Their instructions are not clear about that.
2. Low 120v input. It runs but at lower amps . . .

When I used my 60a PowerMax, input voltage was 122v under full load. Output was connected to several different discharged batteries and dc loads with 3 ft. long, 2 gauge cables. Output current would never exceed 53-54a. Same loads connected to a PD converter produced rated current.

I'm not saying PowerMax converters in general do not produce their rated current. What I am saying it's possible PowerMax may have quality control commensurate with their pricing.

I have no way of knowing about that. You must be annoyed with your unit though. There is a warranty, but I remember with my busted Parallax, it was a hassle where I had to pay to ship it back to them on the off-chance they would find something wrong with it, etc. I chose not to bother. Don't know how it works with PowerMax.

Meanwhile, if the PD was not when using the same #2 cables as the PowerMax, might be worth checking the #2 connections. Must be an adapter to the lug to get it in the #4 converter terminal that could be the culprit.

Back in the day we had lots of posts about PDs not meeting rated amps and failing to hold constant amps in Bulk. Salvo used some graphs to show that eg. Then a guy posted his graph that showed his PD doing ok where he used short fat wire. I never have had a PD to do my own measurements.

BFL13 wrote:
My PowerMax converters (100a, 75a, 55a) have all met and exceeded their amp ratings (103, 76, 56). There are two main reasons for not reaching converter rating:

1. Using #8 output wiring. Needs #4. Their instructions are not clear about that.
2. Low 120v input. It runs but at lower amps . . .

When I used my 60a PowerMax, input voltage was 122v under full load. Output was connected to several different discharged batteries and dc loads with 3 ft. long, 2 gauge cables. Output current would never exceed 53-54a. Same loads connected to a PD converter produced rated current.

I'm not saying PowerMax converters in general do not produce their rated current. What I am saying it's possible PowerMax may have quality control commensurate with their pricing.

My PowerMax converters (100a, 75a, 55a) have all met and exceeded their amp ratings (103, 76, 56). There are two main reasons for not reaching converter rating:

1. Using #8 output wiring. Needs #4. Their instructions are not clear about that.
2. Low 120v input. It runs but at lower amps

EG my 75 runs at 76 off generator, but at 67ish on long #12 cord from stick house.

Same thing with my old Parallax 4455 I had some years ago. It did 55 amps on #8 but did 60 amps on #4.

The PowerMax units I have all ramp up their amps on start-up as seen on the Trimetric, so they reach max amps a tad after getting going.

opnspaces wrote:
I know the PD has a decent following as it works for people. But I'm wondering how much of the higher cost is really goodwill or perceived value and not anything to do with reliability or longevity over any other brand.

Every PD converter I've owned has always produced their rated output within +/- 1a. I purchased a 60a PowerMax converter about 6 mo. ago to use in our home for various projects. The adjustable charge voltage was a big plus. However, it would never produce its rated output. Max current hovered around 53-54a. Probably not a deal breaker for a number of folks, but it's something worth noting. Based on a number of PowerMax reviews I've read, this appears seems to be a common occurrence.

opnspaces wrote:
one last question for any of you who run an inverter generator. Currently my Honda 2000i basically idles when plugged in and charging. I assume this is because the charger is stuck at 13.6 volts.

If I go to a PD 45 or a PD 60 amp I'm assuming the generator is going to ramp up a bit and make some noise. Does your 60 amp charger cause the generator to really ramp up and put out some noise? Or does it still stay fairly low in the decibel range? . . .

Yup, at 13.6v not much of a load--maybe 3-4a.

The Honda 2000 just starts getting noticeably louder as its load approaches 8a. 7a or less, it's still relatively quiet. The PD 45a and 60a converters I've used draw 7-8a and 9-10a under full-load at 14.4v. The PD 45a will ramp up the Honda a bit (the 60a noticeably more), but not as much as it would running an a/c.

I finally decided on and purchased the Powermax unit. My thought was that all three are basically the same as automatic three stage chargers. But with the Powermax I can flip it to manual mode and crank it up to 16v to equalize the batteries from time to time. Now I may never actually do that. But I have the option and the unit was less expensive than the PD or IOTA.

Thanks everyone who posted here and gave me your input.

opnspaces wrote:

I know the PD has a decent following as it works for people. But I'm wondering how much of the higher cost is really goodwill or perceived value and not anything to do with reliability or longevity over any other brand.

If you are looking for a "set and forget" converter, hands down the PD series will do that for you. I do like the lower storage voltage mode of the PD at 13.2V because my RV sits unused for long periods of time plugged into shore power. Very low water use which means I don't have to check the water levels every month as I would if I had a converter that only settled down to 13.6V.

PD should also switch to bulk mode automatically when you apply shore or gen with a partially depleted battery. I know mine does that.

PD does have one strike against it, that is the PF or power factor is not as ideal which means it tends to draw a bit more power than other same amperage other brands. That can be an issue with using a smaller generator. A PD9160/PD9260 can draw more than 1000W at full output because of the PF. May be a bit close with your 2000W gen if you have other 120V items running. For that reason some folks have used a lower amperage PD with small gens.

Iota because of it's higher voltages might deliver a slight advantage to charging a bit faster, it takes more voltage to push more amps back into your battery.. However, the battery will tend to self limit just how much it will accept so any advantage there sort of depends on your type and size of battery.

Both PD and Iota are pretty much set and forget, in most cases, should never have to force modes, just allow them to do their jobs and all will be good.

If you have the need to constantly tinker with charging your batteries then something like the Power max which has the means of manually adjusting the voltage might be your ticket.. Some folks love to tinker with batteries as a hobby (battery maintenance hobby) and some like myself would rather spend time doing other hobby things..

opspaces,

Since they are sulfated I'd try to recover them.