Relay getting stucked

[vicky001.iith]

Hello Everyone,I am controlling a very high load(Air condition type) using a realy switch.But Relay get stuck after continuous operating(ON/OFF) of the switch.
Possible reason:- As high load gets ON.It takes surge current almost 6-7 times of its normal rating.Like a 6A AC takes 60 Amp surge current at Switching ON stage and Relay gets stuck due to high surge current.
I tried to connect NTC in series with load to control the effect of the surge current.I used NTC-2.5D15 which is having current capacity of 9Amps.Relay which i am using is HF46F.
Possible solutions to avoid Relay stuck??

 

[goldsmith]

Hello Everyone,I am controlling a very high load(Air condition type) using a realy switch.But Relay get stuck after continuous operating(ON/OFF) of the switch.
Possible reason:- As high load gets ON.It takes surge current almost 6-7 times of its normal rating.Like a 6A AC takes 60 Amp surge current at Switching ON stage and Relay gets stuck due to high surge current.
I tried to connect NTC in series with load to control the effect of the surge current.I used NTC-2.5D15 which is having current capacity of 9Amps.Relay which i am using is HF46F.
Possible solutions to avoid Relay stuck??

Hi
You must change your relay with a better one ( which can handle more instantaneous current )
BTW for this application triacs can be used too but of course you must take care of snubber for em .


Best Luck
Goldsmith

 

[D.A.(Tony)Stewart]

The Relay contacts should be rated for the HP motor used.
Motor currents reduce the contact current ratings compared to resistive loads.
If you cannot find , check with OMRON specs.

 

[chuckey]

First you must clean the relay contacts, then make sure that they are not damaged by over voltage when they open. If they are then the current only flows through a small area, leading to overheating and welding when they next close.
Frank

 

[ahsan_i_h]

You can use the relay SLA-12VDC-SL-C.

NO contact : 2HP 240VAC (1HP 120v)
NC contact : 1/2HP 240VAC (0.25HP 120VAC)

Datasheet link: **broken link removed**

See the picture below.