Good deed for the day

4-post lift? That's bloody cheap if you do mean 4-post lift - if not, what's a 4-wheel lift?

A lot of us would love to have one in the garage, but sadly, I don't think many of us would have a garage high enough to make decent use of it.

Peter

AstraVanMan ( snipped-for-privacy@Whataloadofforeskinbollocks.co.uk) gurgled happily, sounding much like they were saying :

I wonder if it's like a friend has two of in his workshop - two post, with arms so all four wheels are danglings free.

Or, indeed, 3-phase. (One of friend's is single-phase, however...)

The message from "PC Paul" contains these words:

Would that I had a 3-ph supply to the garage.

The message from "AstraVanMan" contains these words:

You could have one of those pleated pop-up roofs you used to see on Campervans. It'd be dead cool watching the whole roof go up as your car rose into the gods.

Inverters are relatively cheap now, and you get second hand ones on eBay.

Hi Guys,

PC Paul kindly posed the ad here on behalf of a mate of mine.

It is a real '4 poster' and was left over from when their company used to do cars alongside motorbikes.

I was wondering if, depending on the power of the current 3 phase motor, if it could be replaced with a single phase one (I'm guessing there is only one motor)? Machine Mart possibly?

Also I believe the 'freewheel' bit is where you can lidt the car up on the ramp then lift it again off the ramp to get all 4 wheels clear at the same time?

All the best ..

T i m

p.s. This is a genuine 'surplus' item .. ;-)

>

Don't bother. Most of the lifts are only 2 horse motors (about 2kw) and you can easily run a 3 phase inverter from a single phase supply. Usually the inverter is cheaper than the replacement single phase motor.

2HP is about 1.5kW

Indeed, around 250UKP for a 2kW one perhaps. Also likely to be more reliable and better able to provide the starting torque needed for many applications that were designed for a 3-phase motor.

Chris

That is very cheap.

sponix

1496W actually. I round up to the nearest convenient number to be safe - as long as it's less than the magic 3.3kW it'll run off a 13A socket....

Think my father paid about £200 for his so that'd be about right. Was impressed by how small they are now - about the size of a large paperback with some impressive solid state devices on it doing the grunt work.

lol - the last serious inverter I had anything to do with was a 10kW 400Hz

3ph generator on the other end of a 3ph 50Hz motor. All had to be bolted down firmly in it's own brick shed and it cost a fortune!

Well, maybe. If the ring main circuit protection is via a MCB rather than a fuse, you might find the enormous inrush current of these things will cause nuisance tripping.

Of course, if the installation of a garage hoist was to comply with BS7671, (as it should), the circuit should be supplied from a separate circuit. :-)

Chris

Interesting. How long ago was that?

I started my electrical career rewinding/repairing stuff like that in 1962!

Chris

About 3 years ago(!) - testing aircraft systems (hence the 400Hz) on the ground.

The message from Chris Street contains these words:

I wouldn't like to draw that much off the sockets in my garage - not knowing what I do about how the power gets there!

The message from "PC Paul" contains these words:

400Hz to make transformers lighter and more efficient, yes?

sounds like my Grandpa's welding set. That was a five litre V8 petrol motor driving a honking great gennie that produced DC at tens of kilowatts. You could weld armour plate with it if you so desired.

Brick shed was optional but kept the rain off this behomoth.

Yup.

The downside is that reactive power losses are significantly higher as you up the frequency. IIRC directly proportional, so 8x higher than at 50Hz in this case.

You've got to be careful about that with single phase motors. Although the running current may be ok, the starting current will be far higher than that. In practice, 3 hp is about the limit for an induction motor run from a 13 amp plug.