Electrical component question

[duncan]

I am looking for the correct name of a component - poor brain can't think of it.

 

I think I upset my satnav in the TR as the voltage from the battery probably fluctuated too much for it. I know there is a component which will limit / adjust the input of 13 to 16 volts to a constant output of 12v,

 

If anyone can recommend any particular ones, I would be appreciative.

 

Many thanks Duncan

[Paul J]

I think its a capacitor.

Paul

[RobH]

You are thinking of a regulator Duncan. There are two types available - analogue and switching. An analogue regulator is simple but needs to 'drop' a reasonable amount of voltage in order to operate. 16 to 12 is reasonable but 13 to 12 is probably too close a margin for most simple regulators to function. A boost-buck regulator will do what you want and these have been discussed in previous topics on this forum.

This is an example and you will probably find a similar unit at a cheaper price on e-bay. This will take any varying input voltage between 5v and 22v and is adjustable to provide any constant output voltage between 6 and 24 volts.

 

https://www.amazon.co.uk/MagiDeal-Adjustable-Regulator-Stabilizer-Rectifier/dp/B074686XST/ref=sr_1_8?s=electronics&ie=UTF8&qid=1525982116&sr=1-8&keywords=12+volt+boost-buck+regulator

 

 

Having said that, I am surprised your sat-nav is unhappy. I assume you are driving it from a cigar-lighter plug-in lead which will have a regulator in it already. Most sat-navs actually operate on 5volts and the plug-in lead drops the car supply to that level and should be able to cope with minor voltage fluctuations.

Edited May 10, 2018 by RobH

[ed_h]

These are called DC-DC converters or sometimes buck/boost converters. They are plentiful and cheap on Amazon, Banggood, et al.

 

Ed

[Lebro]

 

Having said that, I am surprised your sat-nav is unhappy. I assume you are driving it from a cigar-lighter plug-in lead which will have a regulator in it already. Most sat-navs actually operate on 5volts and the plug-in lead drops the car supply to that level and should be able to cope with minor voltage fluctuations.

I would also be very surprised if the 12 to 5V converter you are using to power the satnav could not handle any normal car generated voltage.

 

Bob.

[RogerH]

Hi Duncan,

my dash cam came with a faulty cable. the 12V to 5V regulator kept going open circuit.

Not common to find new things duff these days.

 

Roger

[stillp]

I agree with the above posts Duncan. Have you tried your satnav with a USB lead from a computer? I'd be very surprised of your battery voltage was high enough to damage it.

 

Pete

[AlanT]

Possibly not the DC voltage but vehicles are full of high-voltage "spikes" arising from switching of wound and therefore inductive components.

 

These spikes are hard to suppress, they contain quite a lot of energy. A bit more than a few bypass capacitors is often required.

 

When I put new brushes in the heater fan on a modern Vauxhall I found it had dual LC filter-sections. You never see this on classic vehicle components because there was no need.

[Dic Doretti]

Hi Duncan

The voltage stabiliser on the TR6 gives a steady 10 volts or you could use a map, reliable and not subject to voltage fluctuations.

Cheers

Richard

[peejay4A]

Unless you have a modern electronic instrument voltage regulator it is not steady 10v. It uses a heated bimetallic strip arrangement which pulses the 12v giving an average of 10v as interpreted by the gauges which themselves have heated bimetallic strips.

[duncan]

Many thanks all, I probably took the wiring straight off the battery (with an inline fuse). The satnav does not work off the computer, which is why I think I fried it. I did like the old girl, she only sent me the wrong way occasionally, always after a period of non use.

[Ian Vincent]

I was talking to someone at the weekend, and he had a TR6 with EFI, he had some sort of voltage stabiliser across the battery terminals to stop a spike frying his ECU. Don't ask me what it was called.

 

Rgds Ian

Edited May 11, 2018 by Ian Vincent

[Hamish]

I was talking to someone at the weekend, and he had a TR6 with EFI, he had some sort of voltage stabiliser across the battery terminals to stop a spike frying his ECU. Don't ask me what it was called.

 

Rgds Ian

Ian

I think it is called Bob

[RogerH]

Many thanks all, I probably took the wiring straight off the battery (with an inline fuse). The satnav does not work off the computer, which is why I think I fried it. I did like the old girl, she only sent me the wrong way occasionally, always after a period of non use.

Hi Duncan,

a year ago last January I bought a dash cam. Fitted it tot he 4A and had about 10ft of cable left over.

I have a fair few of the accessory plugs. So, shortened the cable attached the plug and fried the dash cam.

It was then that I read the very small writing on the original plug 12V in, 5V out - it isn't just a plug, it is a regulator.

 

There are no warnings on the NextBase packaging/box and a simple mention in the paperwork in small print. But i accept it was my fault.

I went back to Halfords and explained what happened - they were not interested.

I mentioned that the plug is not a plug but a regulator - the chap admitted he did not know that.

 

The sadest thing is when I reported this here last year some bright spark jumped in and said 'of course it is 5V it is a USB- ner, ner, ner'

All very well if you know what that or they are.

 

Roger

[DaveR]

You can buy a cigar lighter adaptor with up to two USB 5 volt outputs. If you have a Maplins near you go and have a look before they finally close down as they are selling this type of thing at sale prices.

 

Dave

[tthomson]

You might also consider a varistor, which dumps excess voltage, but they have a maximum energy limit.