Ready Steady Eddy

[EddyCurrent]

1. if the drives are rated for 80 V DC would i get away with an 80 or 70 V DC power supply?(i'm more than likely going to use a 60 V DC like your self. i'm just curious )

You could go higher that 60v but it can rise due to back emf from the stepper motors.

2. if i do use a bigger supply will i have to go with a bigger circuit breaker? ( what determines the size of circuit breaker required?)

The circuit breaker size is related to the current drawn by the system. You need to make sure it's the right type otherwise it will trip every time you power up, type C or D
http://www.neweysonline.co.uk/MCBs/Static.raction

i'm trying to get to grips with the safety relay because i never had the pleasure to wire one but i would like to have one after reading your blog a few times.

Ebay is the place to look but first you need to decide this;
1. operating voltage and AC or DC
2. how many contacts you need and are they NO or NC
3. Safety Category of device. If it's for home use then just about any of the devices will be okay.