What's are these?

Hadenough

Hadenough

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In the process of tidying my wiring and identifying what goes where. I'm calling it dewiring because I'm taking out (redundant stuff) more than I'm putting in. Anyway, I'm trying to identify these

View attachment 38637

Shunt? Heat sink? Any pointers please.
 
The one on the right is a diode splitter.
AKA pair of blocking diodes.
The one on the left is a 'current shunt' i.e. a calibrated low resistance that a remote meter or battery monitor uses to measure the charge current.
 
Thanks all. I take it that the diode splitter is non intelligent (bit like myself) and facilitates split charging rather than "controlling" it in any way.
 
Or just a simple, unintelligent relay, controlled by alternator D+.
If you want to avoid the batteries being paralleled when you are on shore power.
 
BabaYaga said:
Or just a simple, unintelligent relay, controlled by alternator D+.
If you want to avoid the batteries being paralleled when you are on shore power.[/Qhttp://i.dailymail.co.uk/i/pix/2010/11/29/article-1334244-0C486177000005DC-204_468x606.jpgUOTE]
My vsr senses both banks so either the charger or alternator will still actuate the relay after which ever battery is taking the main charge has reached a pre determined voltage / time
Click to expand...
 
My vsr senses both banks so either the charger or alternator will still actuate the relay after which ever battery is taking the main charge has reached a pre determined voltage / time
Click to expand...

That might be desirable or not. VSR's are often recommended here for charge splitting, but IMO it could be worth thinking over if it is a good idea to bring the starter battery online when charging the house bank from shore power. Especially if the house bank is large or the charger is boosting the voltage.
 
BabaYaga said:
That might be desirable or not. VSR's are often recommended here for charge splitting, but IMO it could be worth thinking over if it is a good idea to bring the starter battery online when charging the house bank from shore power. Especially if the house bank is large or the charger is boosting the voltage.
Click to expand...

.... and different versions are available to take into account both needs. Check out single sense and dual sense.
 
VSR's can work well, but rather that a wholesale rewire, why not just check that the battery voltage is monitored by the charging system(s) on the battery side of the diode charge splitter. There's an almost knee jerk reaction against diode splitters on these forums, but when they are wired properly with voltage sensing sorted correctly there is nothing wrong with them. In fact one could argue that VSR's with mechanical parts and contacts will ultimately fail, but the diode might go on for ever.
 
john_morris_uk said:
VSR's can work well, but rather that a wholesale rewire, why not just check that the battery voltage is monitored by the charging system(s) on the battery side of the diode charge splitter. There's an almost knee jerk reaction against diode splitters on these forums, but when they are wired properly with voltage sensing sorted correctly there is nothing wrong with them. In fact one could argue that VSR's with mechanical parts and contacts will ultimately fail, but the diode might go on for ever.
Click to expand...
My diodes didn't go on for ever. I replaced with a BEP VSR and lived happily ever after.
 
Alpha22 said:
.... and different versions are available to take into account both needs. Check out single sense and dual sense.
Click to expand...

That's fine, but if you want single sense, you're forced to let the VSR sense the the starter battery. Which means the large currents aimed at the house bank will go through the relay. Might not suit everyone.

I am not saying VSR:s are bad, only that there are alternatives worth considering.
 
BabaYaga said:
That's fine, but if you want single sense, you're forced to let the VSR sense the the starter battery. Which means the large currents aimed at the house bank will go through the relay. Might not suit everyone.

I am not saying VSR:s are bad, only that there are alternatives worth considering.
Click to expand...
i have a 1,2,both as well if i need to couple the 2 banks.
when we bought the boat the engine battery & domestic were charged via a simple relay, if we were to have had a battery problem with either bank we had no way of accessing say the domestic to start the engine. i installed the Cyrix & the change over switch to give me options
 
I plan on leaving well alone. I have plenty of charging with solar and a water cooled genny and the solar meter tells me the charge of each bank so the alternator charging is pretty much incidental. I just wanted to identify the components to understand what they were doing. Thanks.
 
BabaYaga said:
That's fine, but if you want single sense, you're forced to let the VSR sense the the starter battery. Which means the large currents aimed at the house bank will go through the relay. Might not suit everyone....
Click to expand...
Not if you have all charging sources going to the house bank first and have a large isolator switch in both the feed to the starter battery and the house bank. This allows you to switch off the starter battery charging when on shorepower, and allows you to isolate the dead starter battery if banks need to be paralleled for starting.
 
sailinglegend420 said:
Not if you have all charging sources going to the house bank first and have a large isolator switch in both the feed to the starter battery and the house bank. This allows you to switch off the starter battery charging when on shorepower, and allows you to isolate the dead starter battery if banks need to be paralleled for starting.
Click to expand...

An emergency switch which allows you to start the engine from the house bank is a very good idea.
As is the principal of connecting all charging sources to the house bank first. (Exactly my setup, BTW).
And yes, you can avoid the potential disadvantage of the VSR by opening the starter battery switch when on shore power, if you remember to.
Or you can achieve the same thing automatically by using a simple relay, controlled by alternator D+ (charging light).
 
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