[17AndCounting]

We've installed some electric fence but we have some regular escapees. They don't seem to feel it at all? The others stay clear of it but these ones just wander right through!

I don't know what rating the energiser is but husband has touched the fence by accident a couple of times and says it gives quite a bite! It's polywire strung on electric fence posts, stands about 3ft tall (but they're not going over it they're going through it) with 4 or 5 strands in total per post.

Any suggestions?

[Foobar]

I've had ones like that too, usually the clever ones who realise that if they run fast enough they can get through between the pulses.   Also had ones that jump over it too.
The only way I've found to combat this (both the running through and jumping over), is to get them to touch it with their nose (bribe them to come close to it with food).  It sounds cruel but it might be the only way.

[ZaktheLad]

My horse didn't even respect our electric fencer, despite it giving me one hell of a shock when I touched it that left my arm numb.  He went over or through it so many times that on one occasion he ended up with one of the stakes piercing his sheath and giving him a nasty jagged rip injury    Didn't bother to use it again with him 

[SteveHants]

Use wire, not polyrope - wire gives much more of a kick. Wool pretty much insulates sheep against polyrope.