Thread: Switches any good?

Other than the fact it doesn't appear to be a No Volt Release switch, with which most new machines are now fitted, it should the job.

Added advantage is it will work with a wireless remote control (think dust extractor) which NVR switches won't.

Good price. It appears to have been intended for 120V use, (3.7kW / 30A = 123V), but if it's only switches with no internal electronics it should be fine.

Check this out. (The usual price in Oz?): TBSP-330
( GST is already included. Must be $59 GST. )

Originally Posted by Hermit

Good price. It appears to have been intended for 120V use, (3.7kW / 30A = 123V), but if it's only switches with no internal electronics it should be fine.

So would that overheat on 240V or require work to use on 240V…. I basically just want something that I can splice into the flex on the back of the motor and screw to the bench. Most of my old equipment has to be turned on and off at the power point which means walking to the other side of the garage to where a long extension lead plugs into the wall.

Originally Posted by DSEL74

So would that overheat on 240V or require work to use on 240V…. I basically just want something that I can splice into the flex on the back of the motor and screw to the bench. Most of my old equipment has to be turned on and off at the power point which means walking to the other side of the garage to where a long extension lead plugs into the wall.

I just found another listing, with more info. It's intended for 3-phase. Hence the three sets of contacts. Just use either one or two of the pairs of contacts, depending on whether you want to wire it for double-pole or single-pole operation. (Double-pole is safer, because it disconnects both wires from the supply when off.) Leave the third pair of contacts unused.

Originally Posted by eBay

Name of Product: Power Pushbutton Switch
Model: TBSP-330(CBSP-330 is the same)
Type: 3 Phase
Current: 30A
Power: 3.7KW
Connection terminal: M4
Total Size (Approx.): 90*45*50.5mm(L*W*H)
Material of Shell: Plastic

It should be fine on 240VAC. It's the current that's most important, so keep comfortably below 30A and it shouldn't get over hot. 30A is about 5HP, so a typical 1/2HP to 3HP motor will be no problem, I'd say.

Because they don't list a voltage rating for the unit I would be very wary of using them for mains switching here.

Voltage rating is very important as it establishes the seperation between contact sets in the switch internals, the size and type of insulation barriers between the contact sets, and the open gap between contacts in a particular set. All of these factors are critical in controlling contact arcing when switching inductive loads like motors.

It is possible on first thoughts to deduce that the contacts are rated at 120 volt from the supplied specification 3.7KW, 30 A (W = A x V so V = W/A or 3700/30). My gut feeling from the limited spec is that the unit is intended for switching a resistive load like a set of heating elements, rather than inductive loads like motors which will always cause contact arcing. It is normal practice to provide a significant safety factor for contact voltage and currrent ratings when selecting switches for motors, and to my mind, the lack of a voltage spec means that the units are not fit for the intended purpose.

Despite the fact that the units are also being supplied locally by a wholesaler (Tobins link), I doubt that they are type approved for Australian use and could legally therefore only be incorporated into products where the designer/manufacturer will be responsible for a; establishing that the design parameters are suitable for the application and b; documenting the design and submitting the final product for type approval. In Oz we are generally well protected by our electrical type approval requirements, to the extent that we either forget that it exists, or assume that everything we want to use has type approval for our intended application.

Hope that this helps you, even if it isn't the answer you were hoping for.

I've bought similar from china andnyhey have been fine.

I just wanted to report that I purchased one of those switches referred to by the OP and they look reasonably robust both inside and out. In fact it looks identical in terms of the internal structure to the original switch on my Romac metal cutting bandsaw but is much more robust that the old Romac switch on the outside. I wouldn't be asking it to carry 30A but for single phase 10A it will be fine.

The plastic surround on my Romac switch didn't like the lube/coolant/swarf being splashed around on it too much and eventually part of the plastic surround disintegrated a few weeks ago.
I replaced the Romac switch with a Schiender 16A rated no-volt switch I found for $36 (including delivery) from RadioSpares.
Buy Push Button Switches IP65 DP Panel Mount On-Off Push Button Switch, 16 @ 230 V ac/dcA EICHOFF 3251-20-01/67 online from RS for next day delivery.

Normally priced at $54, at $36 it's pretty hard to beat, making it as cheap or cheaper than many of the chinese no-volt switches being sold mainly through ebay UK.

Originally Posted by DSEL74

…. I basically just want something that I can splice into the flex on the back of the motor and screw to the bench. Most of my old equipment has to be turned on and off at the power point which means walking to the other side of the garage to where a long extension lead plugs into the wall.

Hello,

Not what you were asking but perhaps a viable alternative ? Have a standard cradle beside each machine to house the remote.

I bought some remote controlled power outlets from Aldi - 4 for approx $15ish. Other places will probably have similar.

The gadget is smaller than a double adaptor, it plugs into the wall then you plug your extension cable into the gadget - It is controlled by a remote like a TV remote to switch the power on at the wall.

Some pictures here https://www.google.com/search?q=remo...ed+power+point

No need to walk to far end of workshop. But not a proper safety switch either.


Bill