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SteppIR control wire gauge

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by WA7F, Jan 7, 2020.

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  1. WA7PRC

    WA7PRC Ham Member QRZ Page

    Hams often pay WAY too much for "plug & play" convenience.
    It's not tinned. The barrier terminal blocks are mounted to a piece of 1/8" aluminum sheet (hardware is stainless steel).
  2. WA7F

    WA7F Premium Subscriber QRZ Page

    ”I was unimpressed with off-the-shelf rotator protection devices (that used olde MOV devices), and shocked at the prices. So, I designed and built my own using Transient Voltage Suppressor (TVS) diodes. They're MUCH faster than MOVs and don't degrade with use. They're available in a wide voltage range for cheep. Since I was working w/ 24V AC, I used bidirectional diodes (1.5KE series). Ceramic bypass capacitors prevent rectification. Since I have two rotators, I built two sets into a weatherproof plastic NEMA box:“

    I found the Littefuse 68V 1500W bidirectional TSVs at Mouser. Apparently the SteppIR runs 24 or 35VAC. I’m not sure if mine is 24 or 35 but, an upgrade might be in order if it’s the lower voltage model. It’s still in boxes out in the shop.

    What value of Caps are you running?
  3. WA7PRC

    WA7PRC Ham Member QRZ Page

    In a system that uses 24 VAC, the device needs to withstand VPK (24 x 1.414 = 34 V). The pn 1.5E39CA diodes I used have VBR = 37V. Pn 1.5KE68A has VBR = 64.60V (way higher than needed/wanted).

    They're known as Transient Voltage Suppressor (TVS) devices, not "TSV".
  4. WA7F

    WA7F Premium Subscriber QRZ Page

    Hi Bryan, sorry about the TVS-TSV dyslexia. TSV (through silicon via) is burned in my brain. :rolleyes:

    I made a few assumptions, perhaps incorrectly.
    1. SteppIR operating voltage of 35 VAC
    2. A transient voltage would overcome the extra few volts pretty quickly
    3. Since the TVS clamps (short circuits) above the breakdown voltage a little extra headroom wouldn’t hurt.

    Assuming 35 VAC for the Stepper, do you think the 1.5KE56CA is a good choice with a minimum breakdown of 53.2V?

    A mix of other lower voltages are also needed at the tower for a 2x6 switch, crossover relays & preamps. Some lower breakdown voltage TVSs are needed to protect these circuits.
    WA7PRC likes this.

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