Question about DC voltage and coil resistance relations in relays

[eepty]

Relay is normally rated at DC voltage 12V, 24V, 48V........
When the DC voltage rating increase from 12V to 24V, the manufacturer always increase the coil resistance by 4 times, say from 200R to 800R, to keep the power rating the same.

However, If the coil resistance increase by 4 times and the DC voltage increase by 2 times, the current have to decrease by 2 times. Does it affects the magnetic field? As a result, does it decrease the contact quality?

Thank you

 

[rikie_rizza]

Question about relay

No it doesn't. There's a short math on this calc but anyway...even the contact speed does not change.

 

[avi_e-]

Re: Question about relay

Hi Friend,

Everything will be fine. For that pupose only it is varied 4 times.

Regards,
Avinash.S.

 

[FvM]

Re: Question about relay

Just consider the number of turns doubled with doubled voltage and halve wire cross-section area. With higher voltages, there is a limiting factor by wire isloation thickness.