Twin black max wired to one battery-safe?

[donzi gt230]

I have twin 200s, serial #s say they're '84, but one power head is newer, unknown year. For sake of space I'd like to wire them to run off one start battery which will be wired through a switch to charge the house batt. Can this damage the charging systems; having them wired together? If so, would two start batts. be enough buffer to then connect parallel to a single house batt.? It currently has two start batts. and one house batt. which is connected to charge off one motor which makes it slow to recharge. If having the two charging systems wired together will damage them, is there a way to do it safely?

 

[j_martin]

Re: Twin black max wired to one battery-safe?

Those are probably just rectifier (16 amp) systems. They could be connected in parallel with no problem. I would disconnect and discard any of the little 2 wire regulators that are on some of those motors.

If they've been retrofitted with the 5 wire regulators, they also can be connected together.

The main thing you would be giving up is redundancy. If the battery dies, you're dead in the water with neither engine starting.

hope it helps
John

 

[donzi gt230]

Re: Twin black max wired to one battery-safe?

Thank you John.
They definitely don't have the retrofit. What's the problem with the two wire regulators?
I'll have a switchable 'jump start' for a back-up.

 

[j_martin]

Re: Twin black max wired to one battery-safe?

Thank you John.
They definitely don't have the retrofit. What's the problem with the two wire regulators?
I'll have a switchable 'jump start' for a back-up.

If they don't perfectly match, one might try to sink the output of both engines. They don't stand up well with just one. When they fail, they tend to catch fire. With the load you have on the system, the battery, well kept up, should be all the regulator you need.

hope it helps
John

 

[donzi gt230]

Re: Twin black max wired to one battery-safe?

I unfortunately don't know the difference between a regulator and a rectifier by sight. What I have is a squarish piece with two yellow wires and a red, one yellow has a grey attached also; tach signal I think. This is mounted right next to the starter solenoid. Is that enough for you to ID which system I have?

 

[j_martin]

Re: Twin black max wired to one battery-safe?

I unfortunately don't know the difference between a regulator and a rectifier by sight. What I have is a squarish piece with two yellow wires and a red, one yellow has a grey attached also; tach signal I think. This is mounted right next to the starter solenoid. Is that enough for you to ID which system I have?

That's a rectifier. Some of them have a small regulator on top of the engine also connected. You don't

Max output is about 16 amps, not regulated.

 

[CharlieB]

Re: Twin black max wired to one battery-safe?

Personally, I would go for two starting batteries, reasoning, insurance against a single battery/charging system failure leaving you with a single dead starting battery AND a dead house battery.

Then, to charge the house battery, get two 25 amp diodes from Radio Shack and place them in-line from each starting battery going to the house battery. This way both charging systems are capable and charge the house battery while keeping the house battery isolated from both starting batteries unless you rig a jumper across the diode (in the event of a starting battery failure due to a dead charging system on one motor.

 

[donzi gt230]

Re: Twin black max wired to one battery-safe?

Thank you John and Charlie. My issue for the batteries is space (and weight slowing me down). The current set up is silly: three group 27 deep cycles, two as starting and one house parallel to the port starting. Ideally I'd have a start batt. and two house isolated. Diodes have their ups & downs, maybe on an unregulated system as this it would be good to keep from cooking the deep cycles even if slowing the charge rate, but the start batt. would still potentially see high voltage. Also, simply installing a diode from the start to the house wouldn't solve anything as the house system would still drain the start batts., it would just be slowed a bit. The diodes would have to be wired with the charging system on their inputs and the batteries on their output so it would require 4 diodes to have two start batts. and a house bank. I was planning on using relays or a combiner switch to handle the isolation so when they're all linked there's more battery to absorb the voltage and charging would be as fast as the system can make it. I'll have to do some testing to see where my voltages go in my normal use and decide on the best system. A manual switch is the easy way, but I don't trust my memory for the little things and just know I'd end up pulling the rope at some point. If it didn't take so much to put on the rope I wouldn't care as these motors start easily.