Remote Switch voltage 027 tubular

Discussion in 'G / O / S Scale Model Trains' started by geoeisele, Nov 6, 2010.

  1. geoeisele

    geoeisele New Member

    So, this newbie (not near any hobby shop) ordered online and bought two Lionel remote 027 tubular track switches. Then I found out they use 15 V AC. So far, so good, but the MRC AC transformer I also ordered puts out 18 Volts fixed AC and 0-17.5 variable AC. Will this thing burn out the switch motors immediately? Anyone have a solution if this is, indeed, a problem?
  2. Bill Nelson

    Bill Nelson Well-Known Member

    I haven't messed with AC much having worked mainly with HO and cars, both nominally 12 volt systems (although most cars run at 14.5 V).

    If you were concerned, you could wire in a rheostat , which is a variable resistor, and dial it down, using a voltmeter to get you down into specks. Most likely you will be ok though, check the specifications of other transformers. the switch motors if they are wired in to operate momentarily, should not be greatly affected by the small amount of extra voltage.

    Bill Nelson
  3. geoeisele

    geoeisele New Member

    Thanks a lot, Bill. I strongly suspect you are correct about the transformer not frying the switch motors with a little extra voltage. Otherwise, why would a reputable company like MRC make a transformer that's gonna fry switches? Makes no sense! But I once drove a Ford van with no second gear, in the Rocky Mountains, and didn't find out about the danger until the brakes went out on a steep road! You never can be too careful.
  4. pgandw

    pgandw Active Member

    It's not a problem.

    The O27 switches operate off track power, which is variable voltage AC. Unless you are operating post- or pre-war locomotives at top speed, you won't be using anywhere near 17 volts on the track. When I'm running modern 3 rail equipment (1970s or later), I set up on the 0-11 volts tap of my 1033 transformer, to avoid having everything go too fast.

    Virtually all switch machines use in 3 rail O are the twin solenoid type. These use a short burst of high current to throw the switch. Extra voltage (anything less than 25 volts) simply makes them throw with more of a snap. This is actually better for the coils if the current is shut off as soon as the switch is thrown.

    High voltages are not a problem - except for any indicator lights in the circuit. If you are using consistently high voltages on your switches, put in higher voltage bulbs - 18v bulbs. This will prolong the life of bulbs. Bulbs last longer if used at less than full voltage.

    The real issue with O27 switches has always been cars standing on the non-derailing rails with track voltage turned up. This will send current continuously to the coil of the switch machine, and may cause it to overheat and burnout. The O27 switches - at least all post-war ones I am familiar with - did not have cutoff contacts like their more expensive O, Super O, and Fast Tracks brethren.

    hope this helps

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