4 Attachment(s)
Colchester electromagnetic brake
G/day all, I have a colchester master 2500 and would like the electro brake to engage a bit quicker, it takes about 1 to 1 1/2 seconds after the clutch lever is thrown into neutral before the brake hits the skids and I can see problems ahead.
It might not sound like an issue but when you want to stop NOW !!!!!! it doesn't............
With this lathe when the clutch is engaged and the spindle/chuck is turning power is applied to the brake coil to hold the brake in the disengaged position, when the clutch lever is thrown into neutral power to the coil is switched off , supposedly, and about 1 to 1 1/2 seconds later the brake clicks as the spring pressure applies the brake.
I wouldn't have thought that the capacitor attached to the brake coil wires would hold the brake coil energized for that length of time? The capacitor doesn't appear to be on the schematic so maybe it is the culprit and should not be there ?????
The brake coil operates on about 120 v dc and has 252 ohms resistance. I can't see any other capacitors or timers.
3KIM is the brake contactor.
So what I would like to know is how can I speed this brake application up?
cheers, shed
I know i't probably a bit late but...
Quote:
Originally Posted by
shedhappens
G/day all, I have a colchester master 2500 and would like the electro brake to engage a bit quicker, it takes about 1 to 1 1/2 seconds after the clutch lever is thrown into neutral before the brake hits the skids and I can see problems ahead.
It might not sound like an issue but when you want to stop NOW !!!!!! it doesn't............
With this lathe when the clutch is engaged and the spindle/chuck is turning power is applied to the brake coil to hold the brake in the disengaged position, when the clutch lever is thrown into neutral power to the coil is switched off , supposedly, and about 1 to 1 1/2 seconds later the brake clicks as the spring pressure applies the brake.
I wouldn't have thought that the capacitor attached to the brake coil wires would hold the brake coil energized for that length of time? The capacitor doesn't appear to be on the schematic so maybe it is the culprit and should not be there ?????
The brake coil operates on about 120 v dc and has 252 ohms resistance. I can't see any other capacitors or timers.
3KIM is the brake contactor.
So what I would like to know is how can I speed this brake application up?
cheers, shed
I know probably a bit behind in the times for a post (2017)... but have just bought a master, and having the same issues, re speed of braking.
Did you sort the problem? I am an elec eng... and cannot see why the delay in the brake (mine behaves exactly as yours) unless it is somehow mechanical... but the delay (as you quite rightly mention 1...1 1/5 sec) is very consistent, across all speeds... the "pull up time" only being effected by (what would appear to be) the set spindle speed?
The 'capacitor' you mentioned, is actually a "varistor"... common control item to overcome "transient spikes" such as with DC braking circuits! Stops the collapsing coil voltage stuffing up the bridge rectifier.
Nothing in the circuit I can see can (or would) cause this delay. I am about to attack mine over the next few days to "re-invent" the wheel and make it behave better... and hopefully find out why the delay... as i would like it to "plug brake" also. I cut a lot of threads to 'the shoulder' (mainly plunge cut...yeh i know I'm lazy)... so would like same to work as I think (and would appear you do), stop the thing quickly?
let me know if you still require anything further... happy to help (especially on the electrical side)!
Steve...