Ahh, but they do exist…3pole earth leakages with no neutral. Then where will one use such a thing? But it gets worse:- Why would ‘Hager have a 3pole earth leakage device BD364, BF364, BDC364, BTC364 – I can’t use these for motors and the like, they will trip for nothing, or will they? So where […]
One day an electrician calls me saying the earth leakages he bought is “over sensitive” I bought this new digital tester and they all trip around 22mA. So I say: You do realize that ELD /RCD are subject to temperature variations, so on a hot day we still want to be sure it trips nothing […]
I actually had a call from Schneider technical to assist in selecting a downstream protection sub board circuit breaker. They mentioned a suggestion to put fuses in the board. *This off course the solution to lift the kA rating for the down stream designed equipment. I could not help but to smile and confirm Schneider […]
Mmmm…So we got this feedback from a fuse supplier suggesting we use 2x400A fuses in parallel to make up 800Amp. Why is there something that bugs me about this? And since we are at this…What about using contactors in parallel to qualify for a higher current load? Maybe it just sound wrong theoretically but in practice […]
Lets first confirm we are on the same page:- Surge protection gets installed in parallel from the main supply, so it is inevitable that the wire sizes for bigger installations will be an issue for an installer and secondly:- If there is no protection on the SPD and due to lightning or accident the protection […]
So I get called to confirm if changing from DOL to a softstarter will get a motor started with limited generator power. Is it unfair to respond and say I don’t know – It all depends on the dynamics of the load and the machine design and finally the generator load graph. The caller gets […]
Tags: alternator, genrator, softstarter
What does a star/delta starter do: Imagine a connected big hosepipe and the tap is opened – the full pressure will be available(delta), but what if the pipe is stretched such that the diameter decreases and the pipe grows longer…its the same pipe just differently configured.(star). That’s exactly what it is. When a motor starts […]
Been working with star/delta starters for many years and not once did this cross my mind…I guess those were the days when energy conservation was not an issue.
===>>>OOPS…You are not logged in for this group!
===>>>OOPS…You are not logged in for this group!