I’m finishing setting up my Elite Woodworker & need some help on the power for the shop vac. I’m in the UK so 240v. The PSU has 1no power inlet & 2no outlets for the router & vacuum. There is no 2nd power in for the vacuum that i’ve seen on 110v units but there is a sticker syaing that the vacuum should be on a separate circuit? Given that there is a vac power out socket you would assume ok to use, so, am I ok to run the vac from the PSU? The vac is 1500w & just over 6amp draw.I have a VFD/spindle on a separate breaker. Thanks all.
I guess it all comes down to your breaker – can it handle both the spindle and the vac? I’m not familiar with the details in the UK.
Now, all that said, it’s probably best to keep the vac on a separate circuit just from a noise perspective. The VFD should have good filtering if it’s a quality unit, but when the vac comes on, there is large inductive load which causes transients out of phase from the voltage - that can confuse some components (mostly GFCI).
-Tom
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Thanks for the reply Tom. The breakers should be sufficient, currently 32A. As for the spindle, it’s the 2.2kw water cooled one from PWNCNC. I currently have the CNC on it’s own dedicated circuit, the VFD/spindle on its own circuit and plenty of spare circuits for anything else. I was hoping to power the vac from the CNC PSU outlet as this is controlled by the Masso and so will switch itself on/off when machining. I’ll be running/controlling the coolant via the IoT on the VFD to provide overrun.
Does the risk of interference affect the VFD or the Masso? Or both? I’m assuming that as Onefinity have a relay controlled outlet on their PSU for a vac then any issues concerning interference are either mitigated or simply not an issue?
I found your YouTube channel late last week. I’m only a couple of videos in but it’s a great resource. Keep 'em coming 
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Hi Keith,
I’m using UK FoxAlien Relay Module Relay Switch for CNC Router Machines, for dust extractor
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Hi Keith – very generally speaking, the VFD could be a source of EMI but it shouldn’t travel down the supply lines. The job of the VFD is to take the standard wall voltage (~60Hz), boost or reduce it to an appropriate voltage and then modulate it. It’s the high voltage modulation that creates the EMI as the waveform slaps around the control wires. Most good VFDs will have shielded cables and good filtering - that should control the emanated emissions.
The vacuum on the other hand, is generally a pure inductive load - it creates a ton of electrical noise but (generally) at a much lower frequency. They are generally not filtered in any way and could induce noise into surrounding components via EMI and also through induced currents through the source line. The good news is that specific kind of noise is relatively easy to filter out so most well constructed power supplies will not be bothered and will not pass it to the more sensitive silicone based components.
Long way of saying you should be OK 
You might be able to use an IOT relay to control your vac to keep the source lines separated in some way if you can’t plug your vac directly into the PSU.
Hope that helps.
-Tom
(I’m slowing down on YT to focus on another project that might be of interest to folks here, but too soon to provide details, but thanks for the kudos! 
)
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