Durable Battery Charger

Try the company Lamarche.

I have used their chargers in many exotic applications.

You may need to protect your charger from the corrosive environment....maybe you need a larger battery, or two....Maybe a ups system...$.02

Consider fitting an appropriately-rated auto-reset overload device in the charger output leads.

What you described is a regular saltwater chlorinator that one finds on swimming pools. The electrolysis unit activates whenever the filter pump motor is running.

As Ozzb suggested, ditch the battery. Go to a poolshop and score yourself a power supply.

These are designed for the job, have an adjustable output (chopper on the secondary side of the transformer before the bridge rectifier) and a meter that lets you see if the chlorination rate (current) is correctly matched to the flow rate of the water.

Thanks.

These units are in a remote, third world location with limited resources. The pump runs off a generator but the system is designed, for simplicity to use a 12 volt battery to drive the chlorinator. We can just disconnect the battery charger when pumping water, but the problem is someone ultimately forgets to disconnect the battery an it fries the charger. I will revamp the circuitry and try and protect it by creative switching.

I'm not sure how your engine is coupled to the alternator of your genset.

Given your stated location it may be belt driven. If it is then it is not overly difficult to run an automotive alternator of the PTO to charge your battery and to run the electrolysis cell.

Automotive alternators start at around 45A and 80A alternators (eg toyota camry/Denso) are easily sourced and are much cheaper than equivalent sized rectifiers. This will easily and reliably charge your battery and energise the cell.

If the genset does not have a PTO pulley then maybe your pump is belt driven and you can run an alternator off that if the pump motor is big enough.

Other wise you may need to discipline (training and policing) the SOP possibly with an additional switching arrangement (although removable crocodile clips are a pretty good switch already aren't they?) OR source/purchase/build a bigger rectifier that floats the battery and runs the cell at the same time.

These cells draw approx 20A if I recall.

What is the end use of the chlorinated water in this third world remote location?

The water is used or potable water for about 3,000 people. The generator is a commercial diesel genset. I believe that the system draws 3-5 amps on the 12 volt side which is why we have so much trouble.

Something like this?.....

Hopefully 12V electric start with its own battery.

The automotive alternator on the prime mover will keep its own battery charged and handle your cell power requirements with ease.

Connect directly to the genset's battery via a fuse. The further the cell is from the genset the larger your conductors will need to be.

In its crudest setup it could just be a set of jumper leads connected between the genset battery and your cell battery. (+to+, -to-)

5 Amps sounds too low. Did you measure that? If it is that low why did your battery charger struggle and choke?

We did not measure it. The estimate came from the electrolysis manufacturer. It the system might run for as much as four or five hours hours at a time at the estimated 5 amps. Do you think the charger will still keep up at that kind of a draw? I also do not know about the quality of batteries we can purchase. The airlines do not allow us to transport them so we are at the mercy of what we can find at the local market.

So you haven't operated this yet but you are concerned that the battery charger that you have may be inadequate...

The battery charger I have can run (has run) at 10A continuous duty in tropical ambient temperatures. I don't know what type of charger you have so cannot say. The alternator on the genset will not get tired if you take that route.

I buy new automotive batteries here a lot and they are as good as any anywhere else. Find a reputable dealer at your destination.

Where are you going to put this system together?

It is in Jeremie Haiti and has been in operation for about two years. Everything works fine except the chargers only last six months or so. We have finally settled on just disconnecting the battery whenever the system is treating water but run the risk of running the battery down. The generator normally only runs to keep its own bank of batteries charged (They supply power through an inverter to the whole house.) The charger is powered by the main bank of batteries and inverter. The generator is about 100 feet from the water pump.

The generator normally only runs to keep its own bank of batteries charged

So, you have a rectifier plugged into the generator?

What is the nominal voltage of this battery bank?

What is the power rating of the invertor?

Does your pump run off the invertor too or do you run the genset when pumping?

What type of genset is this?

It wouldn't be a hybrid solar(other alternative energy) setup by any chance?

If you were considering transporting automotive batteries by air then I'm guessing you have a decent budget.....

Instead of a battery charger why not get a rectifier and float charge your battery and run the cell (possibly dispensing with this battery all together)

A swimming pool/spa salt water chlorinator power supply would probably be less expensive than the excess baggage or even airfreight for the battery that you were prepared to pay for.

A swimming pool/spa salt water chlorinator power supply might fail in less than a year though; they seem to have a short MTBF for some reason (domestic duty?) but they are repairable.

A good quality switch mode power supply would deal with the reliability issues. Here's an example of some options and pricing

If there is anything else about your installation that you could share with us it will help with our second guessing.

I am sorry, I guess I should have started at the beginning. It is a 9Kva propane powered generator as part of a future combination solar powered system. The nominal 12 volt battery bank has 12 batteries in the bank. I do not know the rating of the 120 volt inverter. And yes the 120 volt 10 amp water pump normally runs of the inverter as well as lights and refrigerator for the house. The water system not only supplies potable water for the orphanage but we have a public spigot for the village as well.

If the present battery can no longer supply nor sustain the current requirements of the load, it is either under sized or nearing its end of life!

The charger's only duty is to recharge the battery and to put back whatever lost or used-up energy from its stored capacity. Never to supply power to the load!

You need a new set of batteries - not a charger, unless it is already cooked? If it is already burnt, then you need to replace both!