Bypassing Siemens Direct-on-line-starter


Introduction: Bypassing Siemens Direct-on-line-starter

We have all seen this big bad box, which forces us to get up and manually switch on appliances each time there is a power cut.

A simple hack to bypass this is tape the spring method but that method is inefficient as the tape loosens over time and you need to reapply.

So today I am going to teach you how to short and bypass this box once and for all.

Materials required :

  • Wire (preferably thick or a bunch of them together)
  • scissors
  • Screw driver

Step 1: Connections

Open the box with a screwdriver to look inside and with a wire or more do the connections as shown in the figures.

You can unscrew the screws near the wire to force the wires into a notch and then tighten them back so as to assure a tight connection.

Step 2: How the Shorted Circuit Looks

Finally we have a shorted connection which forces the box into auto on.

Hope it helps.



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    14 Discussions


    1 year ago

    Unfortunately your photo is on is incomplete it does not show the whole wiring layout


    1 year ago

    I have a new installation I have 3 brand new Siemens DIRECT online starter l 12 32246 out to the motor on the bloody thing will not start I don't know why it's driving me crazy if I hold the contactor in of Corsa motor runs
    I have the same trouble with us sprecher
    Can I send you a photo of the wiring you can find me on Facebook stew her or just email me directly at her and
    Thank you very much

    Instead of bypassing the contact you can simply do away with the motor starter and install it directly to your service using the appropriate overcurrent protection.

    2 replies

    One can't do that in hostels as they may inculcate serious problems with the authorities. Good point though.

    Another option would be to implement a soft start system reducing the stress on the infrastructure, as well as the supplied equipment.

    BeachsideHank makes a good point. If the power grid barely handles the load during normal use, all the appliances turning on at the same time would easily overload the grid with surge current. If they provided switches with randomly generated timers from 1 to 5 minutes, for example, they could automate the process better for people. At least they could bring up the grid with no load for testing during the first minute that way.

    I think I can see the logic of it's existence; if a power outage is restored, you don't want a lot of high current appliances being energized at the same time or you go down again. This method delays and ameliorates the bringing back online of heavy power consumption units. Bypassing this feature may not be such a good idea after all.

    2 replies

    Thanks for mentioning a serious importance of such a device. I can see why they might have been installed by the authorities.

    But as per the situation we have the ACs of all rooms switching off constantly which is much more of a pain than that you mention. Moreover I am just suggesting a way to make this happen, application's pros and cons have to be thought about by the DIYer

    I understand your frustration, I was just voicing a thought about the impact of not using these devices, but the real answer is for the council to make safe, plentiful energy available to all. If a unskilled group of persons like the Dabbawalas can transport literally hundreds of thousands of meals and return the containers, all to the right location and owners every work day with little mishap, it makes you wonder just what is going on with the well- financed utilities boards. I think we all know the answer to that one though...

    This is a motor starter with start & stop buttons. In short a switch with motor overload protection. Why would you want it on all the time? All you are doing is bypassing the N.O. Aux contact. Also for the looks of it, this starter is not installed to basic NEC code, as you are using NM class seal tight with no fitting or ground and a non rated cable on the load side.

    Places that have frequent power outages often have some kind of back up power supply/generator in the home or business. The purpose of these boxes is to keep generated power off the line for the sake of worker safety.

    1 reply

    Sadly it's not so, atleast here these lines do not have any backup power, and hence it seems to be a strategic way to reduce usage of heavy load appliances.

    This box has a basic function similar to that of MCBs, they sit as an interface between appliance and power supply, if and when the power supply is stopped a switch (sort of relay) is switched off inside which needs to be manually switched on again after power supply is resumed.

    These are an extreme annoyance in India as we have a lot of power cuts and hence we need to go again and again to switch these on every time.

    Hope that clears your doubt.