Electrical question

[rjg30091982]

Hi All,i'm trying to wire in my siren for the IP2 and electrics is not my strong point.i have two relays, but what i'm doing below is not working only one horn is sounding and the other does nothing.i have a switch which powers relay one, this makes the the first horn sound on off on off etc, but nothing else happens, if i take the earth off relay one so it should earth power to relay two to sound the other horn of the off tone neither works.any elecs that can help?? i hate electrics!cheersRuss

[FloridaMike]

If the diagram is correct, the bottom relay has both coil terminals connected to ground . . . There are four terminals on a relay - two are the coil, two are the controlled circuit (the contacts).Relay coil connections: Hot (this is where the switch connects to), Ground (to chassis). Power to the coil closes the contacts.12 volts is supplied to the coil hot terminal when the pushbutton is pressed, relay activates. Release button, no power to coil, relay contacts are now open. (spring loaded.)Relay contact connections: Contacts Hot (may be combined with coil hot above, may be separate), load terminal (switched by relay, this is the switched output to the load).12 volts goes to contacts hot - when you press the button, the contacts close and power is supplied to the load, horn, siren, ejection seat, whatever.This is for a "normally open" relay - no press, contacts stay open. There is also a "normally closed" relay, contacts are closed unless the button is pressed (not as common).You can probably run both horns off the load terminal of a single relay. Use the other relay for the siren.So - power goes to the pushbutton, pressing the button powers the relay coil, which closes the contacts. Power also goes to one of the contacts terminals, pressing the button connects it to the other and then whatever it is you want to control with the button.A relay is just a switch controlled by an electromagnet.If your relay terminals have numbers on them (31, 84, 85, etc.) please advise and I can tell you what wires go where.Best Regards,FloridaMike

[rjg30091982]

Hi mike i see what your saying but you are talking about a switch relay, this is not a switch relay its a 3 pin flasher relay.it should have power, earth and then the pulse from the relay, when i wire it as one horn it will beep like an indicator on off on off etc, its trying to wire the second relay to pulse on the opposite time to get the nee nah effect.its a 3 pin with 49 - 49a and 31 on the relay.my idea was to have the pulse firing one then when the relay switches over to power the other relay but its just not working, i'm doing something wrong here and i just can't see what.Russ

[FloridaMike]

You're not doing anything wrong, it is just that I don't think the flasher relay will give you what you want here.I don't know of any way to wire two three-wire flashers so one is on and the other is off and they alternate. It isn't very hard to do this with a few electronic components (wired as a multivibrator with some big power transistors driving the relays) but I doubt you want to get in that deep.Let me poke around a bit in some electronics catalogs and I'll come back to you.(You do know you can likely get in trouble for impersonating an officer or an official vehicle? They'll string you up by your thumbs for that on this side of the pond, I don't see your local plods being happy about it there either. You could tell them that imitation is the sincerest form of flattery . . . )Best,Mike

[Malc]

This is probably of no help, but all the police 2 tone horns I have fitted to early BMWs and Nortons were of the type operated by compressed air with 2 separate air pipes which supplied either 2 horns on the BMWs and the combined double sided horn on the Nortons. At the time, these were supplied by vehicle development who had the contract for fitting the basic equipment.In Derbyshire the senior officers then asked me if I could fit flashing headlamps and flashing fog lamps which then became a standard requirement.The later K 100's then went on to have the electronic 'wail' and variable tone horns.The standard electric horns, the Fiam type, were fitted with a high and low tone but these operated together.Malc

[rjg30091982]

Hi mike,i think i may have found a flasher relay by Whelen that actually alternates the signal for me so i dont have to bugger about with it myself!ps you cant impersonate a Police officer over here if you are one, i suspect this might be the same in the good old US of A!cheersRuss

[rjg30091982]

Malcthe Fiam / lucas types do operate together as a horn but only as a horn, if you seperate the two tones you will get the siren other wise it's not a siren its just a two tone horn.watch this, this is what i am after, this is a video of an Interpol/Commando with fiam style horns alternating.http://www.youtube.com/watch?v=4X8nYfslZhwcheersRuss

[rjg30091982]

Mike i should clarify though that if you look at the photos of my bike they wil not say "POLICE" or show crests any where,the siren is disconnected on the road and there no blue lamps fitted to the bike so it complies fully with the road traffic act.effectively its a white bike with a yellow line, when i eventually get round to taking them to shows the lamps can be fitted at the shows and the siren fuse put back in.

[Malc]

Russ, That system is before my time! I only started working on Police bikes back in 1983, Just in time for the first Nortons.I remember about 4 types of flasher unit, some had a separate aux connection which (from memory) gave an output opposite to when the flasher unit was on. If this was connected to the indicator warning light, it would flash opposite to the indicators, ie, on when they were off. I can only ever remember it being used on a trailer becuse one of the lads tried one of the later types fitted to the IP2.Malc

[FloridaMike]

Russ,"Whelen" was the name I was looking for. They make all kinds of flashers and alert systems, including the little black box that flashes the beacon on my airplane.If you have the diagram or part number, I'll be happy to look up if this is what you need and how to hook it up.(I was pulling your leg on impersonating an official vehicle, I know you wouldn't do it because you're well aware of the UK regs, definitely better than I am!)Best,Mike

[rjg30091982]

Mike,i think for £20 this might be the best solution.http://www.ebay.co.uk/itm/Premier-Hazar ... wt_952russ

[FloridaMike]

Russ,That's *perfect*.Just what you need and easy to install as well.If you can find one that is dead, I'd like to dissect it and copy the circuit diagram. I could use something similar here.Best,Mike

[rjg30091982]

hope fully it will be ok but its 75 pulses per minute which is going to be a pretty fast siren!!!!!!

[FloridaMike]

I didn't see that part.If it is electronic, the rate can be changed by swapping a few inexpensive components (usually capacitors). There may even be a rate adjustment on or in it.If you can get a schematic, I can say "change this to this" etc.If it is mechanical, there may be another way to alter the rate.This box will give you the nee-nah sound you want for the horns - the siren is a separate item, and I think you just supply power, whereupon it warbles all by itself.Best,Mike

[rjg30091982]

hi Mike,i say siren but i mean horn nee nah, i have a siren on my commander and you need a special control box for that to produce the different tones, wail / yelp and horn etc.I'm just waiting on the Whelen strobes for the bike so i can put it completely back to original, then have to finish off my Hampshire Police commando and then hopefully my other IP2 will be rebuilt and ready to go back to original!i can't get a schematic from the guy i bought this from, he just deals with ex Police stock.i know it can't be adjusted on this type because it is designed for wig wag of headlamps and rear break lights etc the hunt goes on!Russ

[rustynuts]

You could use one of your flasher units to drive a changeover relay, which would cost about four quid.

[rjg30091982]

Hi All,i got the premier hazard headlamp wig wag from ebay and this works fine so i now have sirens! just bought another 2 for the other bikes!cheersRuss