Length of system-tower interconnect

[YTMezoan]

Good morning,

Some years back, we purchased a used metal sputtering system that came with an interconnect cable that's about 100 feet long that connects the system to power supplies and an uninterruptible power source. We've been using the system with no particular issues but are now looking into making a number of upgrades. As our setup is much more condensed than that of the company whom we purchased the system from, the interconnect cable is mostly wound into a coil that sits between the system and the power tower, and we're considering the possibility of swapping out this cable for a much shorter, 10 foot, cable.

Is there any great benefit for us to go through the bother and cost of making this change (the quote we received from a company we have a longstanding relationship with includes 2 full days of labor)? While we certainly don't benefit from having all of that extra cable sitting there, maybe it's a case of if it's not broken, don't fix it?

(Posted here instead of in the metal engineering forum because my question has more to do with the power supply and cable than the precise use of the machine)

Thanks,

 

[waross]

You really haven't given us enough information to go on.
Voltage?
Current?
Frequency?
Duty cycle?
AWG size of cables?
Two conductor cable or more?
Make and model of sputtering machine?

As a general comment, there is generally not a problem when cables are shortened, except if the resistance of the cables is part of the inherent current limiting of the circuit.
You may have to add a reactor to replace the impedance of the removed cable.
If so,that may explain why it will take two days to shorten the cables.
Two days to shorten a simple cable = unreasonable.
Two days to shorten a cable and wire and mount a reactor = reasonable.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[jghrist]

You will be reducing the losses and voltage drop in the circuit. You will be increasing the fault current. You could calculate all of that to see the effect, but I doubt that 100 feet of cable would make that much difference unless it was heavily loaded or if your available fault is close to the rating of the power supply equipment.

 

[YTMezoan]

Thank you for the information. We'll probably take a wait and see approach rather than jumping to make any changes.

 

[itsmoked]

Around here (Silicon Valley) sputtering is often with RF power> When someone is saying "machine and power tower" shortening a cable would mean shortening a microwave guide and dealing with reflected power and a whole mess of related issues. If that's what you have... maybe stay with what you have.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[YTMezoan]

Interesting. I didn't understand why shortening a cable would be such an involved job but was confident that I could find some electrical engineers here that could set me on the right path. Thanks for your help!