Power Conditioner:

The more I ran my coil, and saw others being run, the more I was concerned about safety! I wanted a box which would plug into the mains supply of the particular venue we were running at, that would act as a power distribution point for all the coils that would be fired up, and have an EPO system. This became the 'Power Conditioner'.

It has a contactor capable of taking the full load of the biggest coil and that can be disengaged at the touch of a button, in case of an emergency. It also incorporates mains filters to clean up any interference the coils inject into the supply line. The Conditioner is internally rated at 240VAC @40A, with breakers for protection.

 

At the front It has a main ON-OFF switch, an EPO button, a key activated arming switch, circuit breakers, a connection for the remote EPO circuit and status warning lamps.
Remote EPO connectionCircuit breakersPower activate key switchEPO buttonRed light  -  Output Live!Green Light  -  Output safe!On/Off switch
At the rear of the unit power comes in (with a 'cable live' neon indicator) and out. We have standardised on industrial power connectors which give higher current ratings than normal mains plugs and this also allows us to interchange different parts of each others coils. I did, however, fit one standard 13A socket so we could run other peoples coils too.

The 13A socket on the far left is actually an inverted output, i.e. when the main power is OFF this socket is ON (and vice versa). This is used to run an emergency light so than if you kill power during a run in the dark, you will be able to see immediately.

Output connection  -  16AOutput connection  -  32AOutput connector  -  13AEmergency light feed
Circuit breakersEPO relayEmergency light control relayLow voltage EPO power supplyOn/Off switchMain power contactorMains line filter
In the inside view you can see the high current 'yellow' wiring running between the input terminals to the 32A output connector, via a breaker, the ON-OFF switch and the 125A contactor.

The big block at the bottom of the picture is a 3-phase 20A line filter. The three low current (16A & 13A) output connectors route power through this filter but the 32A output does not.

 


 

 


 

The EPO button is operated by an observer, leaving the coil owner free to run his controls. If someone moves too close to the coil, or a component shows signs of failing or catching fire, the observer will kill the power.

In the case of the building supply failing, e.g. if an RCD breaker trips, when power is restored the Conditioner will automatically be in a safe state and power can only be reactivated by using the key.

The Conditioner was built as a 19 inch rack mountable unit and is then housed in its own flight case. This gives it a professional look and makes for easy transportation.
(The Conditioner was first used at the 'Cambridge 2000 Teslathon' with great success. Because of its design we were able to make use of the 32A triple-phase supply that was available, no problem at all!)