Quality PAT testing.

[ericmark]

App on phone is early 70's only just got calculators started with slide rule.

 

[SUNRAY]

I seem to remember one horse power is lift 4CWT 1 foot in 1 second which electrically equates to approx 3A which I'd alway used as 720W in any calculations I've made for motor overloads etc.

So these memories are from a long way back and just to make sure I'm not spreading shovel loads of power manure (get it - horse power!) I looked at google which says 550 pounds which I'm happy to say is as near as dammit to 4CWT. Electrically though I now see it's more like 745W, an error of 3% doesn't sound a lot but spread across a big plant room could amount to a lot of current. Worse than that, I see efficiency throws an ugly spanner in the works and as most motors are classed as around 75-80% efficient then 1HP will be more like 4 to 4.3A and a 40% error will not go unoticed.
I suspect I have misunderstood this somewhere and assume the efficiency is already included it a motors stated HP rating.

 

[EFLImpudence]

550 lbs. is not really 'near as dammit 4 cwt'. 448 lbs.

 

[JohnD]

Metric hp is less than imperial hp

The one quoted in cwt and feet will be imperial

Metric will be standard now

Power for modern car engines that I have seen is stated in kW

 

[securespark]

My sis had an old Hotpoint WM with nylon wheels riveted in at the back and adjustable feet at the front.

 

[JohnW2]

If a manufacturer does not fit a fuse when needed then the product is not fit for purpose.

That can certainly be argued in the case of most products intended to be used in a country (i.e. most countries) which do not have fused plugs. However, plenty of products which are "not fit for purpose" exist, and in a country in which there are fused plugs (i.e. primarily in the UK) one at least has an opportunity to remedy that situation.

As for 'a fuse when needed", it can be argued that, ideally (i.e. to minimise fire risk) 'appropriate fusing' of any load is always desirable unless the product's normal running current is close to the rating of the circuit's OPD - and, as above, a good few products don't have that.

Kind Regards, John

 

[SUNRAY]

550 lbs. is not really 'near as dammit 4 cwt'. 448 lbs.

oops a slip of the pen there, I meant 5 CWT or ¼T. Even though I wrote it twice

 

[SUNRAY]

My sis had an old Hotpoint WM with nylon wheels riveted in at the back and adjustable feet at the front.

I don't think I've ever known a WM without wheels at the back.

 

[securespark]

My Sammy WM has no wheels.

 

[SimonH2]

I remember 1 HP being 33,000 ft-pounds/minute. At least that's the number dad used and taught me - I've never ever actually needed to do any calculation other than "1hp is near enough 3/4kW".

 

[mattylad]

My preferred HP is brown and on my sausages.

 

[SUNRAY]

My preferred HP is brown and on my sausages.

NOOOOOOOOOOOOOOOOOOOOOOOOooooooooooooooooooooo tomato ketchup everytime.