i think you talk about disturbance / interference. you can use a remote relay / contactor far from your controller or near to your load, this remote relay can be switched via another small relay in the controller.
i think you talk about disturbance / interference. you can use a remote relay / contactor far from your controller or near to your load, this remote relay can be switched via another small relay in the controller.
when you break the load current there will be some interference. That is why you have to keep the relay near to the load far from your controller, also better to use another small relay to switch the load relay. it will give you good isolation. (small relay will handle less current only to switch the main relay)
you can still try to use the transistor & locate the relay far, some time you will have to keep two relays (both) far from your controller to get away from the disturbance. try and find out which works for you.
If you want to reduce the contact arc place a .1 uF (metalized film cap if possible) cap in series with a 47 Ohm 1/2 watt carbon resistor and place that combination in parallel (across) the relay contacts. Commonly called a RC Snubber Circuit. A Google of RC Snubber will bring up all you need to know.