Ducati.ms - The Ultimate Ducati Forum banner

1 - 4 of 4 Posts

·
Registered
Joined
·
11 Posts
Discussion Starter #1
A connector on the cut wires is to be applied. Does the relay care which way around it is switched? Will the relay receive damage if the switch is wired back to front? Is there a non-destructive test I can use on the relay to determine correct switch polarity?

Thanks for assisting. Bit by bit this neglected 916 is returning to a state where I can attempt to start it.

976341
 

·
Excel Addict
Joined
·
5,085 Posts
A connector on the cut wires is to be applied. Does the relay care which way around it is switched? Will the relay receive damage if the switch is wired back to front? Is there a non-destructive test I can use on the relay to determine correct switch polarity?

Thanks for assisting. Bit by bit this neglected 916 is returning to a state where I can attempt to start it.

View attachment 976341
hi there,
That device is called a solenoid, but behaves in the same way a relay does.
i.e. apply power. to the coil and it closes the contacts.
The coil will not be polarity dependent, so connect whichever wire you want to it.
A word of caution though. With solenoids the coil, which is wire wound around iron to create a magnetic field to move the contacts, when your let go of the start switch the magnetic field collapses and a very high voltage spike is induced which can damage electronics = your ECU.
The connection in the wiring harness to the coil should have a diode that overcomes/negates that spike.
if it does not then you should fit one.
As you are in Australia, head down to your local Jaycar and buy a 1N4004 diode.
Next get out your multimeter and put it on the 20 volts DC scale.
Connect it to the two wires in the harness that will connect later to the solenoid coil.
Press the start button so you can work out which wire is positive and which is negative.
Once you know that, you need to connect the diode ACROSS those wires.
One end of the diode, well near the end will have a silver or white band.
That end connects to the positive wire. and the other end connects to the negative.
Once you have done that, connect it to the solenoid coil and you are in business.
 

·
Registered
Joined
·
647 Posts
hi there,
That device is called a solenoid, but behaves in the same way a relay does.
i.e. apply power. to the coil and it closes the contacts.
The coil will not be polarity dependent, so connect whichever wire you want to it.
.
An AC coil have no polarity but logically a DC coil should have no?

Plugged the right way it should pull the contact closed and inverted will try to push the contact away? Just asking, not sure.

Also I have bought before relays with integrated diode, important in this case to wire properly.

Search the web with part number and you should find the electric diagram of your selenoid. Or try it on a battery, should not destroy anything.
 

·
Excel Addict
Joined
·
5,085 Posts
response part 1 - "relay' coil DC - slight chance - read the link.
response part 2 - no - the coil develops a magnetic field and the pulling "direction" does not change with the coil terminal polarity being. reversed.
response part 3 - refer. to the link.
response part 4 - "or try etc" if there was a diode. then you would have a 50/50 chance. of blowing the diode. once blown, the coil would then operate irrespective of power polarity to it.
 
1 - 4 of 4 Posts
Top