Carbatec

[Taffy Evans]

Hi, recently my Carbatec dust extractor system died, no go at all. After over 20 years I was not too upset. It had failed to start on its own eight years ago, so I removed the motor cooling fan and fitted a pully to the motor instead, this allowed it to be started with a rope, Lawnmower style.

Anyway, the repairers said it was a capacitor, and after a month's wait, they had not found one. I tried Carbatec and I was amazed to find that they had one in stock. Problem solved. The rope went into the bin.

Good quick service from Carbatec, thanks.
Taff

[Bristlenose]

Hey Taff, some info for you. Might help, might not. You probably already know a lot of this, but it’s also for anyone who comes upon this post when searching for info on how to test and fix woodworking equipment electrical motors.
Hopefully it helps someone…

I assume it was the fan motor start cap that blew?
These fans usually take a small cap value (competitively), smaller than motor start and run caps.
I had a canfan that wasn’t working a year or so ago, bought a new fan (as I needed an extra one anyway) and when I found the time to get the part, I swapped it out. I checked the cap value, then changed the cap for one out of a refrigeration fan (EBM style) and it fixed the issue.
These small caps can be harder to locate stock on hand, but are so cheap on eBay or wherever that it pays to keep a couple spare.
Some electrical wholesalers may stock them, can’t hurt to call around. But you may have better luck calling a refrigeration parts supplier (actrol, heatcraft, Airefrig). If they don’t have them they should be able to point you at a local place that does.
These caps can cop the brunt of power surges and brown outs, as well as due to lightning strikes; usually indicated by a hole in the capacity itself, or the extrusion of the caps melted internals. Or brittleness in the capacitors housing.
Both run and start caps going at the same time suggests power supply related problem, so check with your local electrical company for local surges, spikes, brown outs or lightning strike. Test the power with a meter from the power point, and again inside the machine where the leads come in and joint a terminal block. 220-250v is usually a good range, too much outside that range can cause issues.

The value doesn’t usually have to be exact, but close is usually good enough. Eg if you have a burned out 1.5ohm cap, a 2ohm would likely be near enough to exactly the same, a 3ohm should work even a 1ohm might work for a while. Just don’t put 80 or 100 ohm in its place, use some common sense (which I assume we all have as luthiers) so the motor doesn’t burn out.
Sparkies will tell you with better authority and info than I can, I don’t understand the finer points of it as I’m not a qualified sparky or fridgey… My knowledge is from 25 years working with refrigeration equipment and learning everything I could from fridgy’s and sparkies working on our equipment.
In all that time, not one fridgey has ever said it needs to be exact. I’ve changed hundreds of run and start caps, often near enough has been good enough to get it going until a new replacement cap can be sourced.

For electrical motors bigger than a fan…
You can get these sorts of industrial capacitors anywhere in Australia… they’re commonly used (and blown up) in commercial refrigeration.
In 25 odd years, 9 times out of 10 if a refrig unit isn’t working right it’s going to be capacitors, wiring between capacitors and circuit board or a relay are probably cooked. Testing relays usually means changing for a known good relay, but you can use a meter to make sure the trigger wire is powered and energizing the relay. When energized, the normally open contacts on the relay close and complete the circuit for the active to flow from power inlet straight to the required components… and normally closed contacts open when the relay is energized, this can mean you can have the one relay disconnecting anything attached to the NC contacts, and closing the NO contacts to complete a circuit, at the same time. Not all relays have both NO and NC contacts.

Same with a lot of electrical motors, like in our woodworking equipment, they’ll operate on the same principles… using run and start caps for the motor, and sometimes relays (to take the constant load off of a switch or controller), which is easily transferrable from refrigeration to pretty much any industrial/commercial electrical equipment.

The parts are easily available to anyone, look for a place that rewinds motors and transformers, they usually have stock of the more commonly used larger rates capacitors.

In perth, I get them from a company called Global Rewinds, located in Spearwood. They’re not cheap, but they’re not super expensive either. What they are is very convenient.
Might not be cheaper than from Carbatec, but sometimes it’s more important to get something fixed that day rather than wait on parts.

Always take pics of how your blown capacitor is wired before removal so you know how to put it back together… remove it and take it to your closest supplier. Call refrigeration parts supply companies too, eg Actrol, as they often have some stock. Or ask any fridgey or sparky where to get run and start capacitors locally… they’ll usually point you in the right direction if you don’t seem like a bloke who’s likely to blow themselves up. They may even have second hand ones in their ute, it’s not something that anyone likes to throw away unless they’re cooked.

If you’re in Perth, I have a bunch of caps on hand at various ratings between like 25 and 80 ohm and *may* be able to help if spearwood is too much of a hike. I also have a bunch of the low cap values for fans. Some new parts, some perfectly good that I’ve harvested from old refrig units being decommissioned. Others have gone out of spec and were replaced… sometimes they go out of spec but are still usable at the new rating. Even temporarily or for troubleshooting purposes.

It’s always a case of test the cap value with a decent meter, the +\- ratio is usually 10% before they’re out of spec, and may or may not work depending on the sensitivity of the equipment it’s being used on and in what role.

When trouble shooting anything with both run and start caps, it’s worth noting that sometimes the start caps go out of spec, and the run cap now being closer in required value will work to start and the out of spec cap will still do the less demanding role of providing running current to the motor, so a simple swap can be a temporary fix. Then replace for new when it arrives. Sometimes this doesn’t work, but it’s usually worth trying.

Starting an electrical motor from a dead stop tends to be calculated 3.5x its nominal current draw; eg a unit that is designed to run at 7.5amps will draw approximately 26.25 amps for a fraction of a second when starting the motor (In refrigeration that’s the compressor, but there’s plenty of wood working equipment that use big motors that probably use run and start caps), then idles at 7.5amps meaning a 10amp plug is still acceptable for the equipment. This is why some electrical motors need both a starting cap and a running cap, to provide that jolt of current to start the motor moving before the running cap takes over.

If it’s 3 phase, it’s more complicated, generally using three active phases, a neutral and an earth. Often at higher voltages than single phase, commonly see 440v; usually at 20amps or 32amps per phase, sometimes higher.
Extreme caution is advised when going near 3 phase. Make very sure there’s no power, 3 phase voltage and currents are not to be trifled with (see; arc flash, also, how much more dangerous the power supplied by 3 phase power is to the human body).
Never ever rely on a circuit breaker, RCD or safety switch to prevent electrocution. It should save your life, but it’s not worth the risk. Plenty of damage can happen in the split second it takes for the switch to trip.

Also, either single phase or 3 phase, test capacitor values out of the circuit.

VERY IMPORTANT
*Make sure the caps you are removing from the equipment and are about to handle are discharged* either by doing what my teachers taught me (the dodgy way) which is arcing the terminals with a screw driver… but a lead with alligator clips and a resistor will do the job better, in theory, but both will stop you from copping a solid boot.

I recommend using a volt stick, they’re cheap and are a good way to double check your circuit isn’t energized. Test your volt stick on active power first to make sure it’s working. I have a fluke volt stick in my glove box from having to locate and test (sometimes troubleshoot) power on clients premises, which isn’t something I do much anymore, but it’s a handy thing to keep close, just like a good multi meter. Again, I have a fluke clamp meter, doesn’t need to be super fancy, just reliable.


Hopefully this info helps someone when troubleshooting and repairing their equipment.

If you’re having issues, are in Perth and need help, msg me and I’ll do what I can to help. I can also try and walk anyone through it over the phone if not in perth, as long as there’s a multi meter on hand.

Regards,
Nick.