paul connor Posted January 24 Share Posted January 24 Hey all, I have a Wolf HS 90 which is 24v and no issues with my wide track trailer which is also 24v (bulbs). I have an issue I have been trying to work the easiest solution for, but cannot seem to get there. I would also like to use my civilian trailers which are 12v, without having to change bulbs or use a trailer board. Is there any NATO to 12v convertors available, or any way I could switch the voltage down to 12v when needed? I have a NATO to civi lead I made, so that is no issue but the reduction in voltage is. Any ideas? Quote Link to comment Share on other sites More sharing options...
MatchFuzee Posted January 24 Share Posted January 24 LED 10v-30v bulbs can be used on both 12 volt and 24 volt lighting systems. https://bedazzledledlighting.co.uk/product-category/led-bulbs/ Not sure about the use of LED bulbs in trailers as they are technically a vehicle MOT failure. Quote Link to comment Share on other sites More sharing options...
radiomike7 Posted January 25 Share Posted January 25 A simple way is to use a set of 24V relays to switch 12V supplies to the lamps, if you have access to relays you can make it up yourself or use one of these: https://www.ebay.co.uk/itm/284187851514 A downside is that a 12V supply is required and usually tapped off the link between the two batteries. This can cause one battery to discharge over time so a better way is to use a 10A 24V/12V dropper as used in trucks. The LED route is a possibility but remember that it is a legal requirement to have an indicator failure device which will not work by just fitting LED bulbs. Quote Link to comment Share on other sites More sharing options...
MatchFuzee Posted January 25 Share Posted January 25 8 hours ago, radiomike7 said: simple way is to use a set of 24V relays to switch 12V supplies to the lamps An American ready made converter:- How It Works Takes power from the tail light circuit, wire #21, and converts it to 12 volts. That 12 volt power is fed into relays that are triggered by wires# 22-460 and 22-461, the left and right stop/turn circuits. The 12 volts from the power converter and relays are fed to a civilian trailer connector. The tractor versions have additional relays that provide separate turn and stop lighting circuits for semi trailers. https://www.xm381.com/Mil_to_Civi_Info.html Would it show indicator failure? Quote Link to comment Share on other sites More sharing options...
Rob.Brindley Posted January 25 Share Posted January 25 Not looking for business but I work in the automotive trade. This is what we supply for 24v vehicles towing 12v trailers: 160502 Trailer Connecting Unit (hc-cargo.co.uk) Quote Link to comment Share on other sites More sharing options...
radiomike7 Posted January 25 Share Posted January 25 29 minutes ago, Rob.Brindley said: Not looking for business but I work in the automotive trade. This is what we supply for 24v vehicles towing 12v trailers: 160502 Trailer Connecting Unit (hc-cargo.co.uk) Ideal, but over £200. Quote Link to comment Share on other sites More sharing options...
Rob.Brindley Posted January 25 Share Posted January 25 3 minutes ago, radiomike7 said: Ideal, but over £200. If you're in the UK, I can supply at £110.00 + vat inc postage. Don't want to brake forum rules and I'm certainly not looking to advertise our business but I know we fit supply these regularly so I can vouch for their quality. Rob Quote Link to comment Share on other sites More sharing options...
utt61 Posted January 25 Share Posted January 25 19 hours ago, MatchFuzee said: LED 10v-30v bulbs can be used on both 12 volt and 24 volt lighting systems. https://bedazzledledlighting.co.uk/product-category/led-bulbs/ Not sure about the use of LED bulbs in trailers as they are technically a vehicle MOT failure. They're only an MOT failure if fitted in headlamp units designed and type approved for halogen bulbs and on vehicles which have been type approved with such. It is not an MOT test item in any other light unit (at least not yet as far as I know) although it is technically illegal in a type approved light unit designed for an incandescent bulb on a type approved vehicle. I don't think even now trailers need type approval (do they? Happy to be corrected) in which case suitable LED bulbs would be fine. Quote Link to comment Share on other sites More sharing options...
mammoth Posted January 25 Share Posted January 25 Have been down this track with 24v Volvo semi trailer, led bulbs mess with the indicator circuits so back to changing set of bulbs. As suggested the way to go is to use the truck converters which are solid state (no relays) however ones on ebay in Aus only have 6 circuits so no reverse light. So you have two trailer sockets on the tow vehicle, one for each voltage. Quote Link to comment Share on other sites More sharing options...
paul connor Posted January 26 Author Share Posted January 26 Thanks for some informative replies and ideas. Thanks also Rob for the offer, but alas I am in Germany. I am thinking now along the lines of this (attached image) 7 pin to 7pin 24v-12v reducer. My idea, currently, is to mount this on a bracket in the rear of the Wolf by the radio power supply. I have a spare NATO to 7 pin lead from a wide track trailer which I have used to tow civilian trailers with my other 110 (12v), I can use this to connect to the WOLF plug on the cross member through the radio porthole on the Wolf rear roof section into the reducer. From the reducer then back out of the porthole to the trailer with a standard 7 pin coiled cable. This should hopefully work and I have all the parts other than the reducer. This would then just be plugging in two leads which already have the holes in the rear of the Wolf for radio cables. I will let you all know how successful this is when I get it installed. Thanks again, Paul Quote Link to comment Share on other sites More sharing options...
Rob.Brindley Posted January 26 Share Posted January 26 7 hours ago, mammoth said: Have been down this track with 24v Volvo semi trailer, led bulbs mess with the indicator circuits so back to changing set of bulbs. As suggested the way to go is to use the truck converters which are solid state (no relays) however ones on ebay in Aus only have 6 circuits so no reverse light. So you have two trailer sockets on the tow vehicle, one for each voltage. You can buy inline load resistors (usually quite cheap (£6 ish)) that will solve that problem for you. Just fit them inline in the indicator circuit and the vehicle will see resistance that it's supposed to. Quote Link to comment Share on other sites More sharing options...
radiomike7 Posted January 26 Share Posted January 26 5 hours ago, Rob.Brindley said: You can buy inline load resistors (usually quite cheap (£6 ish)) that will solve that problem for you. Just fit them inline in the indicator circuit and the vehicle will see resistance that it's supposed to. Not inline Rob but across the LED to lower the resistance seen by the sensing circuit to the level of a conventional bulb. Quote Link to comment Share on other sites More sharing options...
Mk3iain Posted January 26 Share Posted January 26 3 minutes ago, radiomike7 said: Not inline Rob but across the LED to lower the resistance seen by the sensing circuit to the level of a conventional bulb. Here is a kit on eBay, there are many others but it gives you the idea... https://www.ebay.co.uk/itm/134799774909?var=0&mkevt=1&mkcid=1&mkrid=710-53481-19255-0&campid=5338268676&toolid=10044&_trkparms=ispr=1&amdata=enc:1UyByeFvSS9GmUSP2fU-yRw9&customid=CjwKCAiAzc2tBhA6EiwArv-i6ZMz2kjjbHH86XBqZ_89nXCAAkAeGI7SxSZsRzISZTQ2KuWX_0xzfhoC9XQQAvD_BwE Quote Link to comment Share on other sites More sharing options...
radiomike7 Posted January 26 Share Posted January 26 45 minutes ago, Mk3iain said: Here is a kit on eBay, there are many others but it gives you the idea... https://www.ebay.co.uk/itm/134799774909?var=0&mkevt=1&mkcid=1&mkrid=710-53481-19255-0&campid=5338268676&toolid=10044&_trkparms=ispr=1&amdata=enc:1UyByeFvSS9GmUSP2fU-yRw9&customid=CjwKCAiAzc2tBhA6EiwArv-i6ZMz2kjjbHH86XBqZ_89nXCAAkAeGI7SxSZsRzISZTQ2KuWX_0xzfhoC9XQQAvD_BwE Thinking about this again, the conventional indicator failure circuit is detecting the presence of an intact incandescent bulb and would only work if the resistor failed, not the LED. Quote Link to comment Share on other sites More sharing options...
Mk3iain Posted January 26 Share Posted January 26 1 minute ago, radiomike7 said: Thinking about this again, the conventional indicator failure circuit is detecting the presence of an intact incandescent bulb and would only work if the resistor failed, not the LED. True, it will not show a failure of the LED as the resistor will still be developing a current. But then the chance of a failure in either is remote especially compared to an incandescent bulb. As far as an MOT is concerned there will not be a warning light and the indicators should be working. Should not be a problem. Quote Link to comment Share on other sites More sharing options...
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