Why was old switchgear so complex?

[fizzy]

Looking at old lathes and milling machines etc.
It seems to me most of the stuff in there can be bypassed and isn't necessary.
Watching a video from This Old Tony he says the same.
Was power dirtier and more unreliable in the old days or was it factory legislation?
I can understand on huge machines but a Bridgeport with a 2hp motor isn't much of a load.
Or a lathe with a similar motor.

 

[zx9]

Looking at old lathes and milling machines etc.
It seems to me most of the stuff in there can be bypassed and isn't necessary.
Watching a video from This Old Tony he says the same.
Was power dirtier and more unreliable in the old days or was it factory legislation?
I can understand on huge machines but a Bridgeport with a 2hp motor isn't much of a load.
Or a lathe with a similar motor.

I guess it is the complex relay logic needed to protect both the machine and user from the user, non of it will have been put there for the amusement of the designer.

 

[123hotchef]

some one has disconected the saftey switches from my Boxford unless the wires were never installed

 

[Seadog]

They were not fitted on the MKI, other than to the motor cupboard on the AUD.

 

[brightspark]

some one has disconected the saftey switches from my Boxford unless the wires were never installed

never bother with safety switches that operate on doors open the only safety foot switch I have is on a scrap cable stripping machine I have its lethal if it pulls you in and cable wrapped round your wrist it don't bear thinking about it would happen that quick

 

[123hotchef]

They were not fitted on the MKI, other than to the motor cupboard on the AUD.

the micro switches are in the head stock where the backgear lever is

 

[mtt.tr]

never bother with safety switches that operate on doors open the only safety foot switch I have is on a scrap cable stripping machine I have its lethal if it pulls you in and cable wrapped round your wrist it don't bear thinking about it would happen that quick

Can have some details on that, as i have loads of cable ready.

 

[brightspark]

heres the old post its now got a 3 phase motor and got a gearbox and chain drive on it https://www.mig-welding.co.uk/forum/threads/home-made-scrap-cable-stripper.20137/

 

[mtt.tr]

heres the old post its now got a 3 phase motor and got a gearbox and chain drive on it https://www.mig-welding.co.uk/forum/threads/home-made-scrap-cable-stripper.20137/

That is brilliant, just needs an out feed and a sheer

 

[brightspark]

the cable has to be cut in 6 foot lengths it comes out that fast no chance of keeping up with it

 

[Seadog]

the micro switches are in the head stock where the backgear lever is

That's because you have a MKII or MKIII

 

[pressbrake1]

Can have some details on that, as i have loads of cable ready.

I ll buy cable of decent length!

 

[pressbrake1]

I guess it is the complex relay logic needed to protect both the machine and user from the user, non of it will have been put there for the amusement of the designer.

Exactly , modern more compact contactors etc will save space but short of using a plc nothing has changed

 

[dannyp]

relay logic takes up a lot of space and looks complicated it isnt once you know what everything is doing and why wire it yourself from scartch to do the same it'll look just as complex to anyone else but as you know what it all dose it wont look complicated to you

 

[Spark plug]

Also you find with old kit, they used various voltages for different control circuits, ware as new kit will generally use 24VDC for everything. The 24VDC also being supplied from a single switch mode power supply, doing away with various transformers and rectifiers.

 

[ronan]

I do have to admire the quality and workmanship in the older electrical stuff. There was a lot of it about in Kevin street tech in Dublin when i was there. It had been donated or obtained when old places upgraded or closed down. Huge electric motors, switch gear etc. Most of it made in the UK, Germany and America.

 

[northwest]

Also you find with old kit, they used various voltages for different control circuits, ware as new kit will generally use 24VDC for everything. The 24VDC also being supplied from a single switch mode power supply, doing away with various transformers and rectifiers.

This. All sorts of bespoke transformers and other kit to power up the power as it were. Modern kit is, as you say, mostly 24v DC and this simplifies everything. To a degree.

 

[pressbrake1]

Ive used thermal imaging to fault find on big relay logic cabinets
Saves a lot of time unless yhe machine has been broken down all shift and cold!

 

[pressbrake1]

My last employed machine tool builder job was for this lot until it was relocated to serbia .
This stuff could be a headache with the plc/cnc hybrid systems
Funny how when I worked there the owner wouldn’t even look at me but since Ive had my own shop he talks to me like a equal!

 

[mtt.tr]

I ll buy cable of decent length!

Mostly old rubbish that ive dragged out. But i do tend to collect alot of pointless lengths of new stuff