Xantrex DR 3624 voltage output

davecharles · August 2012

I have a self installed and self designed pv system(oh no) on my remote Island cabin in NW Ontario. I've been using it for 6 years with few problems until this year. I have 4 200 watt fixed Sharp PV panels (About 30 volt output). A Xantrex C40 charge controller, A Xantrex DR 3624 inverter, and 12 105ah deep cycle batteries (6 24v pairs). After lurking around this forum for a while I know the system needs to be changed so your suggestions are welcome.
Now for my question, This year I have had 2 different televisions give problems. These are older TVs so the problems may just be that they failed from old age. The first one went within days by heating up when in use then eventually let out all of the smoke that kept it working. The second one, a little newer works for an hour or so then starts turning on and off on its own (ghosts). I suspect the MSW inverter is the cause but how do I check? I have an inexpensive multimeter that shows 98 volts at every receptical in the cabin. Is that about standard for reading MSW on a RMS meter? Are there any other checks I can make on the Inverter. As I make improvements on the system I would like to replace the inverter last (most expensive). I would like to change to a mppt controller first if the inverter is still good. Everything else works well in the cabin and the old TV's arent expensive so no great loss. (I just brought up another one the other day)
Dave

SolaRevolution · August 2012

Re: Xantrex DR 3624 voltage output

98 vac is a typical reading for a modified sinewave inverter with a non-true RMS meter. There may be nothing wrong with your DR but some electronics will die from it. I suggest you replace it before your other TV gives up the smoke-ghost or before you get any new appliances.

BB. · August 2012

Re: Xantrex DR 3624 voltage output

Very possible a tsw inverter would fix the problem. The sharp edges of a msw inverter plays heck with inexpensive power suppress.

The other issue with vmp 30 volt panels. In cold weather they will work ok. Up north, that is probably why you get good battery life.

Placing the panels 2 in series with a mppt type controller would be a good fix, but can you justify the $500 or more cost.

-Bill

Cariboocoot · August 2012

Re: Xantrex DR 3624 voltage output

Here's another little problem you have: "12 105ah deep cycle batteries (6 24v pairs)". Six parallel sets are not going to share current evenly no matter what.
That's 630 Amp hours @ 24 Volts, so you have another little problem: your 800 Watts of panel is about half of what is needed to recharge that battery bank properly.

Gosh, we're just full of bad news today. Sorry.

Photowhit · August 2012

Re: Xantrex DR 3624 voltage output

Cariboocoot wrote: »

Here's another little problem you have: "12 105ah deep cycle batteries (6 24v pairs)". Six parallel sets are not going to share current evenly no matter what.
That's 630 Amp hours @ 24 Volts, so you have another little problem: your 800 Watts of panel is about half of what is needed to recharge that battery bank properly:

More likely a problem with math, 3 strings of 4 batteries would give you 12 batteries and a 24 volt system, 360 Amp hours, which wouldn't be too bad. They are called T105's but I believe they are 220 Amp hour batteries now? So 660 Amps hour.

Might try a small 300 watt inverter for your electronics?

Cariboocoot · August 2012

Re: Xantrex DR 3624 voltage output

Photowhit wrote: »

More likely a problem with math, 3 strings of 4 batteries would give you 12 batteries and a 24 volt system, 360 Amp hours, which wouldn't be too bad. They are called T105's but I believe they are 220 Amp hour batteries now? So 660 Amps hour.

Might try a small 300 watt inverter for your electronics?

Well I read twelve 105 Amp hour batteries (six 24 Volt pairs), not "T105's" which aren't the same thing.
It is entirely possible to have 105 Amp hour 12 Volt batteries, unfortunately.

Blackcherry04 · August 2012

Re: Xantrex DR 3624 voltage output

The DR will make you a wonderful battery charger with it's 70 AMP output and you can get a TSW 3000 watt / 24 V Inverter for $900 or so without all the bells and whistles and be good to go.

Photowhit · August 2012

Re: Xantrex DR 3624 voltage output

Cariboocoot wrote: »

Well I read twelve 105 Amp hour batteries (six 24 Volt pairs), not "T105's" which aren't the same thing.
It is entirely possible to have 105 Amp hour 12 Volt batteries, unfortunately.

I stand corrected, and you know how hard that is!

I've got to work on my reading skills!!!

niel · August 2012

Re: Xantrex DR 3624 voltage output

Photowhit wrote: »

I stand corrected, and you know how hard that is!

I've got to work on my reading skills!!!

isn't getting older fun?????? NOT.

davecharles · August 2012

Re: Xantrex DR 3624 voltage output

Thank you for all the replies,

You mostly confirmed what I already suspected. My battery pack is (and will be for a while) 12 105ah batteries size 27 made for a local farm store by exide (6 pairs) After reading info on the forum I understand that the configuration is less than optimum. I'm trying different wireing configurations to make them a little better. I would like to bring up two more 240watt sharp panels to add to my PV array. Then if I change to a MPPT controller to handle the extra amps and convert all of the wattage from the panels I would be closer to what I need. Other great suggestions (less expensive) will be greatly appreciated.
Dave

Cariboocoot · August 2012

Re: Xantrex DR 3624 voltage output

Dave;

Probably the cheapest thing to do is re-evaluate your loads and see if you actually need that much battery bank. It's easier to take some out than to add more in. Then evaluate the batteries themselves. Charge them individually if necessary and see which ones come up and stay up the best. Use them and disregard the rest. You'd be amazed at what you could run from 210 Amp hours @ 24 Volts, which is a lot easier to wire up evenly. See the Smart Gauge wiring diagrams: http://www.smartgauge.co.uk/batt_con.html

Never use method #1. Number two is good for one parallel set and for what you've got now (six in parallel) only method #3 would stand a chance of working. At best your existing array would support three parallel sets of these batteries (315 Amp hours).

And yes, sometimes dropping batteries makes the whole system start working much better. Seems counter-intuitive, and yet it often works.

Xantrex DR 3624 voltage output

Comments

Categories