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I have a double pole 30 amp breaker controlling a 230 volt load that I need to replace. I cannot obtain one at this moment; perhaps tomorrow but maybe next week.

Either way, I have two good used 30 amp breakers that I could put in place of the 30 amp double pole.

Will it be okay for me to do this if I take the tie bar off of the old breaker and re-use it?

I have already pulled the tie bar off and have the two breakers ready to go. Hoping that this will be okay!

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For this to work, the two single breakers must pull power off each bus leg to give you 240VAC. If they pull off the same leg, you only get 120VAC (parallel feed). Check to make sure they use alternate bus connections when they're side-by-side.

If the breaker handles have a hole, I've seen a cut nail used to link them. They must be linked so both legs shut off for the obvious reason.

  • Yes, this is an important distinction. My panel is designed with alternating legs. This is a double pole relay designed for 230 volt loads. My desire to re-use the tie bar from the 2 pole relay is exactly for the purpose of not having to use a different less suitable connector (a nail). Not saying a nail won't work but it seems more likely to fail. – Gabriel Nov 28 '14 at 4:12
  • As long as the circuit details (one pulls off L1 and the other pulls off L2) are taken care of and the tie bar stays securely in place when installed AND disengages the other breaker on trip, you should be home free. – Fiasco Labs Nov 28 '14 at 4:25
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Okay, a few caveats first.

The two single phase circuit breakers are to be identical in the following aspects:

  • Manufacturer
  • Ampacity (30A, 40A, etc)
  • Approximate age
  • Known good
  • Same size on all faces

Furthermore, I believe the following should be observed:

  • The circuit breakers being joined must not be adjacent to empty slots (the tie bar may try to slip / fall out) in the breaker panel.
  • Similarly, if this temporary repair cannot be made with absolute certainty that the breakers will not be allowed to separate during installation/ removal or during their temporary installation than this temporary repair should not be made. I was able to securely join my breakers together with electrical tape thus prohibiting any separation.

Finally, the following must be understood clearly:

  • This is a temporary repair. It is likely not code compliant and may result in loss of life, property or severe injury if not done correctly.
  • This repair is made in lieu of simply installing two breakers with matching ampacity because of the need to simultaneous disconnection of both phases on 230 / 240 volt equipment. Leaving one phase energized on a 230 / 240 volt circuit can be dangerous to life and property!
  • Always verify disconnection of service to any breaker before attempting to replace it. Failure to do so may result in injury or death!
  • This is a temporary repair!!! A suitable replacement two pole breaker must be installed at the next available opportunity!

Now to answer my question...

Yes, if done carefully this is suitable temporary repair... if the above criteria are met.

While there is an internal mechanical linkage tying together a two pole breaker (see below)

preliminary results indicate that the tie bar will indeed sufficiently disengage (not trip!) the second breaker thus having the effect of simultaneously disconnecting both phases to the load.

My only concern is that 'sufficiently disengaged' may not preclude current passing by arcing. I am sure that is the reason for the internal linkage on a two pole breaker. However, this repair is being made on the service for the heat pump which will likely not go long after tripping before being noticed and reset / disconnected.

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Why would you even bother? Handle ties are just a convenience item. They will not turn two single-pole breakers into a common-trip double pole breaker. Stick a piece of tape over the two breakers, to make it clear where they are, for the short period of time until you get a proper 2-pole breaker.

  • Because I am replacing a 230 volt breaker. I will add that to my question, thanks. – Gabriel Nov 28 '14 at 1:36
  • I hope that the need for a tie bar will be obvious now? – Gabriel Nov 28 '14 at 1:37
  • With all due respect, I do not agree. What you say about them not them being the same is true (beyond the obvious even). I drilled out the two brads mechanically linking the bad two pole breaker and can see the internal trip linkage. However, setting the (1/2 two pole) breaker to tripped using that linkage and then setting one single phase breaker to the same "throw angle" results in the disconnection of the single 30 amp (infinite resistance on ohm setting). So, I am going to go ahead with the tie bar. Knowing both phases will disconnect will help me sleep tonight. – Gabriel Nov 28 '14 at 2:29

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