I won't be at my machine til this weekend. I don't think our machines are wired the same but if you send me your email address I can email you the diagrams I have also did you see the link for the manual in the thread? There's a table wiring schematic in there aswell
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Got My First Machine!
- Thread starter Izzy
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- Apr 30, 2015
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Great thread! I hope yous guys get your stuff all sorted out. Agree with everything here and learned a little too. What are the "heaters" for anyhow (asked Scotty on Star Trek)
Mark S.
Mark S.
- Joined
- Feb 8, 2014
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- 11,176
The provide the overload protection for the motor. When they get too hot, they trip the overload relay thus shutting down the motor. They have to be sized correctly for the particular motor and motor starter.
- Joined
- Dec 8, 2013
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- 2,651
Induction motors have to draw several times their rated current when starting but if they keep drawing that much current for too long they will catch fire. Ordinary circuit breakers cannot both reliably pass the starting current and reliably trip if it continues for too long. Thus each motor gets its own overload protection:
http://www.electricneutron.com/motor-control/types-of-motor-overload-relay/
http://www.industrial-electronics.com/ind-mtr-cntrl_004.html
Small motors often have specially-designed fuses wired into the armature. Sometimes these "fuses" are self-resetting, and sometimes they're just fuses. Very small motors are often designed so that they can stall without overheating enough to be a hazard.
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- Apr 4, 2016
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- 959
Joe,
It appears that the two large components on the right side of your photo are the reversing magnetic starters which contain the heaters. The heaters are the six silver colored components under the "Bridgeport" name. There is a screw at the top and bottom of each heater which connects them to mag starter. The thing that puzzles me is that it appears that one of those mag starters isn't being used. The line and load side of the one on the right have no wires connected them. Looks like someone has had their fingers in there. You really need to see if you can locate the electrical schematics for that machine.
Ted
Ted,
Thanks for the input - you are correct. I was just out in the shop investigating and finally figured out the heaters (see photo). The unused magnetic starter (right in photo) was apparently for an optional second head. On the other machine, there is an equivalent unused starter but no option for heaters on it.
I removed this heater from the above starter.
Note the place to mount a second head on this unit.
This sticks out enough that I have bumped my own head - pretty hard a couple of times.
I have tried to locate schematics for these machines but have only found some that were close.
If anyone has schematics and/or maintenance manuals they are willing to email to me, I'd appreciate it very much. joe.w.robertson@gmail.com
The schematic that I have indicated C-H type starters and that was the number I was looking for which is why I couldn't locate the heaters. In fact what I have on both machines are Sylvania starters. For the 480v machine, the heater number is 2446 (active starter) and 2435 (inactive starter). For my 240v machine the heater is 2438.
Googling for Sylvania (Joslyn Clark) heaters, I found the following ratings:
These numbers are counter intuitive as a 480v motor should run at 1/2 the 240 v current. I have found different numbers on these depending on where I look though (1 phase, 3 phase, starter size). There are others - 2444 (11.9 amps) and 2445 (13 amps).
The (Reliant) motor plate on the 480v machine indicates 12 amps at 230 volts. Perhaps the 2446 heater is actually OK on this machine?
For the running 240v machine, the (Emerson) motor plate indicates 10.9 amps at 230 volts. Must be a more efficient motor on this one. Sounds like the 7.03 amp heater is under rated on this machine.
Does anyone have a schematic with a table for Sylvania type starter overload heaters and a 4hp motor (4 digit heater numbers like 24xx)?
Joe
Thanks for the input - you are correct. I was just out in the shop investigating and finally figured out the heaters (see photo). The unused magnetic starter (right in photo) was apparently for an optional second head. On the other machine, there is an equivalent unused starter but no option for heaters on it.
I removed this heater from the above starter.
Note the place to mount a second head on this unit.
This sticks out enough that I have bumped my own head - pretty hard a couple of times.
I have tried to locate schematics for these machines but have only found some that were close.
If anyone has schematics and/or maintenance manuals they are willing to email to me, I'd appreciate it very much. joe.w.robertson@gmail.com
The schematic that I have indicated C-H type starters and that was the number I was looking for which is why I couldn't locate the heaters. In fact what I have on both machines are Sylvania starters. For the 480v machine, the heater number is 2446 (active starter) and 2435 (inactive starter). For my 240v machine the heater is 2438.
Googling for Sylvania (Joslyn Clark) heaters, I found the following ratings:
2435 -- 5.34 amps (480v machine inactive starter)
2446 -- 14.3 amps (480v machine active starter)
2438 -- 7.03 amps (240v machine active starter)
2446 -- 14.3 amps (480v machine active starter)
2438 -- 7.03 amps (240v machine active starter)
These numbers are counter intuitive as a 480v motor should run at 1/2 the 240 v current. I have found different numbers on these depending on where I look though (1 phase, 3 phase, starter size). There are others - 2444 (11.9 amps) and 2445 (13 amps).
The (Reliant) motor plate on the 480v machine indicates 12 amps at 230 volts. Perhaps the 2446 heater is actually OK on this machine?
For the running 240v machine, the (Emerson) motor plate indicates 10.9 amps at 230 volts. Must be a more efficient motor on this one. Sounds like the 7.03 amp heater is under rated on this machine.
Does anyone have a schematic with a table for Sylvania type starter overload heaters and a 4hp motor (4 digit heater numbers like 24xx)?
Joe
Does anyone have extra knobs like those in the first photo or know where I can buy them? They are about 3/4" dia. I need them for the 240v machine (second photo).
If I can't find the knobs, I'll try to make them using delrin rod but I'd rather have the original. I wonder how well the delrin will bond to the surface of the broken knobs.
Joe
If I can't find the knobs, I'll try to make them using delrin rod but I'd rather have the original. I wonder how well the delrin will bond to the surface of the broken knobs.
Joe
- Joined
- Feb 8, 2014
- Messages
- 11,176
If you pull the panel out and look at the manufactures name on the switch, you should be able to find them on Ebay or a local electrical vendor. They look like standard 30mm switches, but could be 22mm (mounting hole size). Can't really tell in the photo.
Here is an option: https://www.automationdirect.com/adc/Shopping/Catalog/Pushbuttons_-z-_Switches_-z-_Indicators
Here is an option: https://www.automationdirect.com/adc/Shopping/Catalog/Pushbuttons_-z-_Switches_-z-_Indicators
Wow! I've really missed alot! So much more good info! Im really starting to think these machines where built to order you seem to have alot of things my machine doesn't and the more people I come across who have these machines the less in common I find with my machine, aside from the standard 4j head and 11x59 table. mine doesn't have a coolant pump ive heard from a few sources and seen a video on YouTube with a power knee/z-axis option but I'm pretty sure I dony have that either. I'll have to email you those schematics in the morning as I'm just getting to bed! Lol