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  1. Soupercollider

    SELV 24VDC Power Supply - Measuring 90V AC!

    Thanks for your replies, everyone. I've been reading up on highZ measuring equipment and why it's bad for what I'm trying to do. I've tested the PSU again this time with a 10k pot between +ve and earth and varied the resistance. Straight away the voltage dropped to less than 2V and kept...
  2. Soupercollider

    SELV 24VDC Power Supply - Measuring 90V AC!

    Thanks FreddyNurk, I hadn't actually thought about the impedance of my DMM (it was a DMM, not a scope that I was using). Mine doesn't have a lowZ option for measuring, but one of my collageaues might. I'll have to check it out when I got back in to work tomorrow. Now that you mention it, I do...
  3. Soupercollider

    SELV 24VDC Power Supply - Measuring 90V AC!

    I haven't got the copy of the standard it in front of me right now, but I don't recall seeing anything in there as far as allowing capacitive potential. I figured it was pretty cut and dry when it said (paraphrasing): It pretty much says the same thing in AS/NZS 3000 for SELV..
  4. Soupercollider

    SELV 24VDC Power Supply - Measuring 90V AC!

    Hi Everyone, I have been arguing with a supplier of mine about a 24V DC power supply which is supposedly SELV compliant to EN 60950. When doing my usual testing of SELV supplies I measure the voltage across any two conductors on the DC side to ensure they do not exceed ELV levels (as one should...
  5. Soupercollider

    Cable protection for Class 30 overload application with soft starter - MCP or thermal magnetic MCCB

    But you're hopefully going to set it to 6xLRA for 30s (Class 30), or something more specific to the motor specs (locked rotor current and locked rotor time). Assuming that the starter will allow these parameters? And hopefully this cable is sized correctly to the motor, if not, then you're...
  6. Soupercollider

    Cable protection for Class 30 overload application with soft starter - MCP or thermal magnetic MCCB

    i don't know about SHOULD use magnetic only, but you certainly can use it. Your cables and contactor should hopefully already be selected based on your Class 30 expectations, so overload protection doesn't need to be too drastic and can be handled by the softstarter (provided you set the FLC and...

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