Charge rate for Progressive Dynamics PD 4645?

pezvela wrote:
How are you all measuring the amps that these chargers are putting out?

with my trimetric. to see total amps I just turn off all the other 12V draws in the trailer so full PD output is going to the battery.

Just chop the positive cable leaving the converter, bring both ends to an analog meter near the converter, or better,....bring both ends to a shunt that comes w/ a 50 amp digital volt meter, or a combo dig V/A meter such as the photo. Then run 18 ga speaker wire to the meter mounted anywhere you want it. The photo shows an inexpensive $15 meter off ebay, works great for a couple years now. No need to buy hi $ meters for monitoring converter output.

pezvela wrote:
So, that's measuring right at the battery from the charging section or that's a measurement of everything the converter is putting out?

It measures whatever current is going into or out of the battery. At the time that photo was take the 12V draw was less than 0.5A for things like the stereo and LP detector.

So, that's measuring right at the battery from the charging section or that's a measurement of everything the converter is putting out?

pezvela wrote:
How are you all measuring the amps that these chargers are putting out?

I have a Blue Sea Systems digital ammeter in my TT.

How are you all measuring the amps that these chargers are putting out?

I have the 45a unit in two trailers. One has about 15ft of #4 wire to the battery on the positive side and about 2ft on the ground side to the frame. Charging 4 Trojan T-125's.

The other has about 4ft of #4 to the positive side and 2ft on the ground side. Charging two Trojan T-125's.

The first will give me a max of about 40A, the second will give me 45A. If the first was a pair of GC I suspect max current would be slightly lower.

Why the difference?? Cable resistance. PD doesn't have a voltage sense at the battery and in bulk mode charger output is 14.6V that could turn ito 14.4, 14.2 or lower at the battery terminals depending on cable resistance. And battery acceptance current is highly dependent on the voltage at the battery terminals. I get 60A for a long time with this combo, but it pretty much eats up all the output of a honda 2000.

So to answer your question. It depends.
a) cable voltage drop
b) what type and how many batteries your charging
c) how discharged the batteries are.

My 4655 will put out ~55A in bulk (±13.6V) or boost (±14.4V), so I would assume that a 4645 will do 45 amps.

pezvela wrote:
I live in Mexico. Buying at home is always more expensive. I love it when things go out, while traveling in the States!

Trying to reduce weight, as much as possible. I think I will take a chance on a brand new PD-4645 lasting a while. If it does go, I'll go back to relying on the solar panel for recharging, while I get it repaired. I can even have the solar charge my truck battery with flipping of a dip switch.

I dont have a manual for my 7345 (yes, that's what I had) but on the inside of the cover, it states that the "average charge rate" is 5 amps, whatever that means.

That is the 7345 meeting a government rule. It goes on to say in their blurb on that figure, that there is no realistic rate to list, because they have no way to know what other loads you may be running as well as battery charging which only gets what is left over. So they wrote down a fake number just to satisfy the requirement.

I can get my 7355 to do 56 amps output running a load if I am not charging a battery. Charging a battery is fewer amps where that 13.8v is not much higher than the battery voltage. You need a spread between the two voltages to get amps.

I live in Mexico. Buying at home is always more expensive. I love it when things go out, while traveling in the States!

Trying to reduce weight, as much as possible. I think I will take a chance on a brand new PD-4645 lasting a while. If it does go, I'll go back to relying on the solar panel for recharging, while I get it repaired. I can even have the solar charge my truck battery with flipping of a dip switch.

I dont have a manual for my 7345 (yes, that's what I had) but on the inside of the cover, it states that the "average charge rate" is 5 amps, whatever that means.