Is 6 gauge wire enough?

[SkyBound]

I have twin Trojan T-105 6V batteries on the tongue and the Progressive Dynamics PD4655 converter upgrade mounted in the original converter location. Is the stock 6 gauge wire running from the batteries back to the converter sufficient? I would estimate the converter and batteries are about 10-12 feet apart.

[Bassdogs]

Originally Posted by SkyBound

I have twin Trojan T-105 6V batteries on the tongue and the Progressive Dynamics PD4655 converter upgrade mounted in the original converter location. Is the stock 6 gauge wire running from the batteries back to the converter sufficient? I would estimate the converter and batteries are about 10-12 feet apart.

Not clear as to why you did a converter "upgrade" but why would you need heavier cable between converter and battery? Understand that cable gauge will affect 12V power loss but twin 6'vs is still pushing 12V into your system and simply has an increased storage capacity [AH's]. If you are wanting to supply power to an inverter, I would suggest as short a run as possible between battery and inverter but that doesn't have anything to do with an upgraded converter.

Can you supply more info.

[oldmanAZ]

I salute your converter change. If your factory converter was like my WFCO, it really is a poor battery charger for boondocking.

What was the original converter amperage? I am assuming (hate to do that!) it was less than the 55amp Progressive Dynamics PD4655 converter. I also assume you are concerned with the added charging amperage being too high for the 6 gauge wiring and you won't be pulling more from the batteries through the existing 6 gauge wiring.

BTW, I am considering the same change for next season, but don't know which Progressive Dynamics unit to install due to questions regarding the OEM wiring.

[RoyBraddy]

When i did the same MOD with WF-8945 COnverter/Charger I changed the cable from the converter to the Power Distribution Panel and the 12V Battery Connection with 4AWG size cables.

I also changed the 12v FUSE mounted in the same battery line close to the Battery terminals to an 80AMP size fuse.

Using a clamp-on DC AMPMETER I see around 55 AMPS being drawn when my three GP24 12V Interstate batteries in parallel are first hit with 14.4VDC coming from my PD9260C. Your T105's really want to see 14.8VDC Boost charge voltage but all will work fine using 14.4-13.6-13.2 charge modes from your PD4655 just maybe take another 30 minutes or so to get the charge state up to its 90% charge state. After 15-20 minutes my DC charge current drops back to around 6-8 AMPS DC for the three 12V Interstate batteries as they start taking on charge...

The inline fuse should be higher rated then the DC OUTPUT AMPS coming from the Converter/Charger unit otherwise it will blow on you...

I don't know off-hand what the 6-gauge wire size will hold up using 12V at 55AMPS DC CURRENT - Just to be safe I replaced my 8-gauge wiring I think it was with installed a 4AWG size cable. I purchased my cables from ANCOR but they are also available from AMAZON. Also ANCOR Brand precut sizes with ring terminals are available from AMAZON.

My four installed 12V Interstate was originally installed in late 2008 with my new Starcraft 14RT series trailer and I lost one 12V battery right away from boiling out battery fluids just using a single mode ELIXIR 30AMP Converter/charger. This is when I got the WF-8900 series Power Distribution Center with the WF8945 45AMP Converter/charger unit. Then I found out it would never go into smart mode charging so i replaced the WF-8945 unit with my currently used PD9260C 60 AMP Converter/charger unit. My POPUP trailer has a great DC Converter/Charger now with many 120VAC Circuit breakers and 12VDC fuse positions.

My remaining three 12VDC Interstate lasted until just last season 2014 where they will not hold charge anymore. I am presently wanting to do a Battery upgrade using two groups of T105 batteries giving me 12VDC at 440AHs capacity. Got the high dollar metal box already completed and done all of the internal wiring with meters and switches etc... Just saving up monies now to purchase four each TROJAN T105 6V 220AH batteries.

My battery upgrade story haha...

Roy Ken

[SkyBound]

Thanks everyone for the input. My original converter was the WFCO 8955 which is 55A and my new PD 4655 is also 55A. I'm more thinking of when I use a generator to recharge the batteries through the converter... I don't want to have to run that generator all day just to get the batteries to 90%. In my mind a larger wire will allow the batteries to charge up more quickly, right? I haven't tried it yet using the existing set up with the original 6 gauge wire mostly because I don't have an inverter generator yet.

[barryg]

6 gauge wire can carry the 55 amps but at the limit near as I can tell, real question I think is how much loss is there over that distance that is why everyone wants them as close together as possible. I just did a quick check with an online calculator and found the following
14 volts dc over 15 foot run on 6g wire at 55 amps calcs to a loss of .65 or 13.35 volts is what ends up at the far end of the wire a 10 ft run equals .43 loss or 13.57 volts
Same thing with a 4g wire calcs .41 loss or 13.59 at 15 feet or .27 loss or 13.73 volts at 10 feet

[SkyBound]

So basically even though my converter is putting out 14.4V during charging, the batteries themselves are probably seeing under 14V by the time the power gets there, correct?

[oldmanAZ]

Originally Posted by SkyBound

Thanks everyone for the input. My original converter was the WFCO 8955 which is 55A and my new PD 4655 is also 55A. I'm more thinking of when I use a generator to recharge the batteries through the converter... I don't want to have to run that generator all day just to get the batteries to 90%. In my mind a larger wire will allow the batteries to charge up more quickly, right? I haven't tried it yet using the existing set up with the original 6 gauge wire mostly because I don't have an inverter generator yet.

The problem I've seen with the WFCO is that it doesn't stay in 'bulk' mode nearly long enough.

Members on this site that have replaced their WFCO converter with the Progressive Dynamics converter report their battery(s) reach fully charged quicker than they did with the WFCO.

[barryg]

yes, based on my understanding of electricity caveat, I am not a licensed electrician or an electrical engineer nor did I sleep in a holiday inn last night