PSA - Primeweld Cut 60 plasma cutters

There is a reason that the USB cable, torch firing cable, and THC cables are the specific lengths that we provide.

The longer a USB cable is, the more susceptible it is to EMI interference. Our USB cable is just long enough to reach from the CNC electronics enclosure to the laptop stand mounting area, with enough slack that a set of additional ferrite chokes can be added if necessary.

Adding length to the torch firing cable is possible, but doing so may cause a very slight delay between the time that the MCB commands the torch to fire versus when the plasma cutter actually receives the command and fires the torch. In most cases, pierce delay is set to only a fraction of a second, so even a slight command delay could result in misfire. Someone who is aware of this and wants to extend their torch firing cable could negate the command delay by increasing their pierce delay.

Adding any length to the THC cables is not recommended at all. THC reports a very small voltage signal to the motion control board in real-time so that the Z-axis can make quick standoff distance adjustments based on how the arc voltage is changing. This voltage signal needs to be as accurate as possible in order for live voltage to reflect the true arc voltage, and reported as quickly as possible in order for the Z-axis to make real-time standoff distance adjustments that are correct. If any of the THC cables are too long, two different issues may occur:

  1. The signal might be reported to the motion control board too late, causing the Z-axis to delay its movements.

  2. The added length may cause the THC cable to act as an antenna for EMI, which will increase the amount of voltage that is being signaled to the motion control board. The motion control board will think that the arc voltage is higher than it actually is, affecting the way it calculates which standoff distance adjustments to make.

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