Should I fit a voltage regulator

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pcatterall

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I think that overvoltage has destroyed my portable TV! and I recently read that certain LED instalations had melted due to overvoltage. I checked my outlets and had 22volts!!, then I checked my multimeter!!, it was reading far to high but,still, I am seeing very high voltages through the boat.
Is it sensible to fit a voltage regulator somewhere which will ensure that the voltages coming to the equipment are reasonable.
I guess I would just need to locate the lead that comes into my control panel and fit the unit on that ?
I can estimate the max load that would be required. Are these things expensive and can anyone recommend a model and even a good supplier.
Many thanks
 
Not enough information. Is the high voltage from the batteries, shore power or anything else (Solar panels?)
There is little point in fitting a regulator to overcome a problem that is caused elsewhere.

First step is probably to get an accurate reading from a reliable meter.
 
Rigger Mortice said:
Not enough information. Is the high voltage from the batteries, shore power or anything else (Solar panels?)
There is little point in fitting a regulator to overcome a problem that is caused elsewhere.

First step is probably to get an accurate reading from a reliable meter.
Click to expand...

I refer to the the high voltages when solar panels or shore power charger are in use The BM1 is reading up to 15volts and this is what I am getting at my DC outlets.

I have changed my meter and ditched the other one.
Thank you
 
pcatterall said:
I refer to the the high voltages when solar panels or shore power charger are in use The BM1 is reading up to 15volts and this is what I am getting at my DC outlets.

I have changed my meter and ditched the other one.
Thank you
Click to expand...

If you haven't yet physically thrown away the old meter then, assuming it is a digital type, it might be worth changing the battery. A low internal battery causes high readings.
 
pcatterall said:
I refer to the the high voltages when solar panels or shore power charger are in use The BM1 is reading up to 15volts and this is what I am getting at my DC outlets.

I have changed my meter and ditched the other one.
Thank you
Click to expand...

PV panels - use an MPPT controller to limit volts to about 14.4 float.

Charger - check it hasn't got dip-switches to allow for a lower voltage - some charger manufacturers recommend 14.8v for open lead acid batteries - IMHO too high a voltage level. If it's still putting out 15.0 volts I'd suggest replacing it with one that does allow you to set voltage levels and absorption charge periods. Most chargers revert to 13.5 volts when they've done their job.

Of course, if you have a failing battery, it could lead to the charger sensing an undercharged battery and carrying on whacking in current.
I'd start with drop-testing all your batteries, individually, and then recharging each to see if it's holding charge.
 
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pcatterall said:
I refer to the the high voltages when solar panels or shore power charger are in use The BM1 is reading up to 15volts and this is what I am getting at my DC outlets.

I have changed my meter and ditched the other one.
Thank you
Click to expand...

What size are your panels? Do they have a regulator? What size is your battery bank?
Have you checked the shore power charger?

What readings do you get if you switch everything off and leave it for half an hour?
 
My LCD tv went down and I suspect that it did not like the 14-15v put out by my solar panels. I bought a cheap voltage stabliser and no problems since.
 
ahabdonal said:
My LCD tv went down and I suspect that it did not like the 14-15v put out by my solar panels. I bought a cheap voltage stabliser and no problems since.
Click to expand...

Yes, thanks, I have heard many similar stories. Rather than buy a device for each bit of kit I thought one master regulator would be better. There is a controller on the panels and I will check my charger.
Thanks all.
 
Has anyone got a link to a stabiliser that would be suitable to fit in the 12v power outlet circuit? Had a quick look but its a mine field. I think all is ok but lately there have been a lot more expensive gadgets being used on-board so better to be safe.
OR
Does my x-split charger thingy sort out all the problems so not worry?
 
pcatterall said:
I refer to the the high voltages when solar panels or shore power charger are in use The BM1 is reading up to 15volts and this is what I am getting at my DC outlets.

I have changed my meter and ditched the other one.
Thank you
Click to expand...

Have you checked the water level in the batteries ?
At 15V they should be boiling wildly
 
As said you need to make sure that your battery voltage is not too high. This will damage batteries and other things.
However the easiest/cheapest way to reduce the voltage is to use a couple of silicon diodes in series. These drop about .7 volt per diode mostly regardless of current. 2 or 3 should make things really safe. Use a switch to bypass if you are not using a charger or engine running. ie battery volts are low. The didoes can be bought cheaply with any sort of current rating I suggest perhaps 20 amp. Voltage rating will not be a concern. The diodes can be in series with most of your domestics and even engine instruments for protection.
Otherwise the buck/ boost regulator from Amazon might be a good bet to protect sensitive gear. I would not be so concerned about LEDs. Only the resistive current limiting cheap ones can be damaged. But then they are very cheap. I doubt a fire is likely.(High Adrian!!)
good luck olewill
 
I purchased a couple of these units from ebay. http://www.ebay.co.uk/itm/DC-DC-Sta..._Measurement_Equipment_ET&hash=item25683232d0

I have run a bunch of bench tests, loading them up to 8 amps or so and they regulate very well and appear to have a decent efficiency, worst I got was about 83% best about 92%. Quiescent current is <10ma. Supplies are not isolated ( gnd is common to input and output ) but the casing is isolated.

I have not had time to test RF interference a, because my spectrum analyser is on loan to someone and b, i have so much else going on.

Provide your total current draw is below 10a ( tv will be 5 or so! ) you should be ok.

I have used one to run the led's lighting and other 12v circuits that i'd like protected from spikes and too much variation on my boat.( leds, engine control instruments, phone chargers, pc power supply, sms tracking system ) So far i have no rf interference issues.
 
Thanks all,
First thanks for the tip on the meter, yes the battery was at fault and a new one indicates that I dont really have 20 volts on board. The highest I have seen after some careful monitoring has been 14 volts but usually 13.8 on peak charge.
However my telly did blow up!! I know that I could get a device for each bit of sensitive gear but thought something controlling all the domestic 12v stuff would be better.
WilliamH..... there was a recent scare on here about melting LEDs hence my query.
Thanks again all
 
The only problem with regulating the power supply down to 12 volts is that any LED's designed for car use will be optimised at around 14 volts and some electronic gizmo's also need a higher voltage. I've got chargers that just won't do their job if they are driven at only 12 volts.
As always, there are compromises with these things
 
Thanks guys, all good stuff!!
Is the device indicated a bit OTT? I really only need to ensure that I dont have 15 volts(The max I have seen on the boat) going into my 12 volt equipment I guess that 13 volts would be fine so I dont need 'protection from 40 volts' or need to work equipment from 8 volts.
Thanks again
 
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