Those Wacky Manufacturers

Status
Not open for further replies.
iwire

iwire

Moderator
Staff member
Location
Massachusetts
I was working on a piece of equipment from England the other day, it had something to do with a magnetic table on a press.

I had to work on the units output cables, they where 11 conductor 16 AWG cables. I noticed that one pair of conductors was being used in parallel I wondered why.

After looking at the labeling on the unit I noticed that the output was 90 amps for .5 seconds.

So every so often the pair of 16s and the 16 amp rated plug on the end of it get a 90 amp shot. It seems to work fine as the units have been in place for many years.

It sure is a different way of thinking then we are used to. :)
 
hardworkingstiff said:
Do you believe it to be dangerous or proven OK?
Click to expand...

I believe (I hope) that an engineer used established formulas to determine the wire sizes needed where we as ECs only look at charts. :)

My point was that we look at conductor sizing from the perspective of long term loads. When you know the load will limited in time that you can do things much differently without overheating the components.

The NEC pretty much allows this for welder supply circuits based on the duty cycle.
 
iwire said:
I was working on a piece of equipment from England the other day, it had something to do with a magnetic table on a press.

I had to work on the units output cables, they where 11 conductor 16 AWG cables. I noticed that one pair of conductors was being used in parallel I wondered why.

After looking at the labeling on the unit I noticed that the output was 90 amps for .5 seconds.

So every so often the pair of 16s and the 16 amp rated plug on the end of it get a 90 amp shot. It seems to work fine as the units have been in place for many years.
Click to expand...
iwire said:
It sure is a different way of thinking then we are used to. :)I like dealing with that type of stuff, that is much more interesting then the normal day to day work. :cool:
Click to expand...
Got your wish?
 
Denis said:
16 amp plug?? what style??
Click to expand...

i would guess one of those stupid blue things that are 5 times larger and 4 times as expensive as they need to be :)

CEE form or whatever theyre called
 
Pierre C Belarge said:
Bob
Do you take pictures of the work/work area that you are involved with?
Click to expand...

No, it is in an area where the customer is very sensitive about photos, trade secret issues.

e57 said:
What exactly was this equipment called - you know how important that is......:roll:
Click to expand...

LOL, :grin:

I can't tell you as I would be wrong. :D

mdshunk said:
It sounds like a shear.
Click to expand...

It might be, it does have a 100 Ton press, I guess if I jammed some stuff in there it might sheer it.

e57 said:
Are you sure it wasn't a press or a punch? Very important!!!!
Click to expand...

It is a press, an injection molding press.

Denis said:
16 amp plug?? what style??
Click to expand...

It is a European 10 pin plug and receptacle.

wireguru said:
i would guess one of those stupid blue things that are 5 times larger and 4 times as expensive as they need to be :)
Click to expand...

Cast gray metal, I will try to find a picture.

Here we go, it is just a bit larger then this one.

8037kc1ws.gif
 
Last edited:
Those are Harting connectors (although there are other brands made that are supposed to mate with them). Both McMaster and Mouser sell them in the US. You can get versions rated for up to 100A per pole, 6 poles in a housing. You can also get versions that have 180 poles in one housing. We use them on our HPO motors rated at less than 20A per phase.

-Jon
 
iwire said:
I was working on a piece of equipment from England the other day, it had something to do with a magnetic table on a press.

I had to work on the units output cables, they where 11 conductor 16 AWG cables. I noticed that one pair of conductors was being used in parallel I wondered why.

After looking at the labeling on the unit I noticed that the output was 90 amps for .5 seconds.

So every so often the pair of 16s and the 16 amp rated plug on the end of it get a 90 amp shot. It seems to work fine as the units have been in place for many years.

It sure is a different way of thinking then we are used to. :)
Click to expand...
Is it that different? If you have a motor rated 10A FLC, you size the conductors for that. But every time you turn it on the circuit will pull 60A, probably for longer than 1/2 of a second. Transformer inrush (which is likely what your machine is doing) can be even higher, as much as 13x FLC) albeit for a shorter duration. That's why we size conductors for FLC rather than maximum current.

If everything were sized for peak currents, we would need a lot more copper mines!
 
Jraef said:
Is it that different?
Click to expand...

IMO Yes, as 90 amps is this units output, not it's inrush current. I understand you point, I have considered that before.

What this unit does is magnetize and demagnetize a flat plate that hold a mold. Once the unit magnetizes the plate the cables are disconnected and the plate stays magnetized. When it's time to change molds the cables are connected and the unit demagnetizes the plate.
 
wireguru said:
i would guess one of those stupid blue things that are 5 times larger and 4 times as expensive as they need to be :)
Click to expand...

Oi! Those connector absolutely rock.

It is great having a single range of connectors rated at 16A, 32A, 63A and 125A that you can tell the voltage of from a distance, that are splashproof (IP44) and dirt cheap, and can stand being tossed about and dropped. And with three, four, and five wire variants.

They are even available with colors defined for USA voltages!!!

Edited to note: Clearly the engineer who designed the "90A through 16A connectors" think is taking advantage of limiting the thermal loadings to those the cable and connectors can handle. I do hope it is with the support of the factory who makes the connectors though...
 
Status
Not open for further replies.
Top