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2 volts relay?

2 volts relay?

2 volts relay?

(OP)
Hi, is there any chance of finding any PCB or plug-in relay working with up to 2.5 volts?

Any suggestions please?

rgds

RE: 2 volts relay?

Over the years I've seen many relays that would reliably pull-in with much less than the specified coil voltage.

In other words, if you don't find a suitable specified product, you might want to try some relays with (for example) 5 or 6 volt coils. To reduce risk, try them at extremes (example: temperature). Also, you'd have to screen them forever in case something changes.

RE: 2 volts relay?

Omron has PCB mount relays with coil voltages of 3 volts with a minimum pickup voltage of 75% of rated voltage.

RE: 2 volts relay?

(OP)
Hi again and thanks for all the input.
I wish to switcn 12V DC.

rgds

RE: 2 volts relay?

How many amperes ? You may want to consider electronic switch -- solid state relay or some custom circuit.

How many do you need ? any other consideration ?
Space, cost, reliability, etc ?
Is the load inductive -- e.g.motor or solenoid --
or incandescent ?


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RE: 2 volts relay?

Just be aware that the 75% nominal rating pull-in voltage allows for a selection tolerance but also for temperature. The TC of the copper coil is about +0.4%/degC. Therefore at 70degC coil temperature you lose a significant amount of sensitivity.

Don't consider a reed switch if you intend to switch more than a 50 W (really 50 VA) load.

RE: 2 volts relay?

(OP)
Amperes and Watts are low (it is a 12V motorbike horn)
I will try some 5 or 6volt coil BUT temperature is expected to rise in the summer...

Any other ideas possibly?

rgds

RE: 2 volts relay?

If you have 12VDC available and you must have a relay for isolation purposes, why not run your 2.5VDC command signal through an optocoupler and use the 12V source to switch its own relay on.

RE: 2 volts relay?

Motorbike theft alarm?

RE: 2 volts relay?

(OP)
Some modification of a Motorbike theft alarm.
Really complicated to describe here.
Thanks for all help and support, I will go for a 5volt relay and if it doesn't work I will post some thread again...

Cheers

RE: 2 volts relay?

If you have 12V then use it.  These low voltage coils need a lot of current and it is far easier to drive a higher voltage coil.

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