I recently upgraded my laser cutter’s cooling system from a basic water pump to an OMTech CW-5200 Water Chiller. My OMTech SH-G460 laser cutter has a built-in safety feature where it won’t start a job unless the pump outlet is powered on. I like this feature because it ensures the cooling system is running before the laser operates.
The issue is that the laser cutter’s pump outlet is a two-prong, ungrounded socket, while the CW-5200 chiller requires a three-prong, grounded connection. I understand that the laser cutter’s pump outlet cannot directly power the chiller—I just need to use that outlet as a trigger for a relay that will allow power to flow to the chiller from a properly grounded source.
Essentially, when the laser activates the pump outlet, I want that to close a circuit that supplies power from a grounded outlet to the chiller. I’d prefer a prebuilt solution, but I’m open to a relay-based workaround if needed.
Has anyone done this before, or does anyone know of a plug-and-play solution that would work?
I’m not sure what that model is, but my Omtech 100 watt has universal sockets by the power cord, 1 of which is labeled chiller. That’s where my CW5200 is plugged in. I leave the switch on the chiller turned on and this receptacle is switched on with the main power switch on the laser. The receptacles are strange looking, but htey accept a standard 3 pin US cord.
They look like this.
Here’s my copy of the 5200 series user and maintenance manuals.
I don’t know how your safety interlocks work. The Ruida has a connection for sensing coolant flow. I wired mine up to the Ruida, so it knows what’s happening with the coolant. If it fails, the Ruida will halt all operations and allow you to restart it where it left off… if it doesn’t tell the Ruida, it’s not going to stop the mechanics.
This is the output of the 5200 series that you can plug into the Ruida.
I suggest using external mains and use the chillers main power switch… After all you’ll only have a couple switches to flip.
The problem I have with these (I have a China Blue 50W from OMTech) is that the e-switch is at or very near it’s current limit using a 120V mains. It’s fine for 220V, but it’s too close for me to it’s upper limit when using 120V mains.
I suggest you don’t load it any further without replacing the e-switch. I wouldn’t run my chiller from the internal mains of the laser.
It’s relatively easy to switch line voltage… I use this Amazon SSR for my fan and compressor… back then it was for both.
I have a third suggestion/idea, I have air, water and light supplied externally and start everything with a simple button on the power strip. Regarding safety, I am very happy with the original built-in flow control/alarm. (It is mounted at the back of the bottom of my machine, right after the water inlet) It has saved my a… 2 times
Thank you all for replaying, turns out I was over thinking the issue. I wound up just using a vacuum relay, plugged the laser into the “tool” slot and the chiller into the “vacuum” slot. I am just keeping the pump switch turned on and the chiller will turn on whenever I turn the laser cutter on.
The chiller should probably run continuously. It takes time for the chiller to reach temperature and most refrigeration systems don’t take lightly to being cycled on/off, usually shortening their lifetime.
Any equipment like this, you should use ssr, not any kind of relay. One of the advantages of a ssr is it switches when the voltage is zero, the mechanical relay has no idea of mains voltage when it switches.
You’re using 120V mains and running all of this load through the e-switch?
Where does this get it’s power? As long as you’re not plugging this into the lasers mains connectors.
No… just when I got work, I turn the chiller on, let it all the pieces cool down to the temperature I wish to use it. When it’s warm outside, it needs to cool down a while.
When I get done with the laser, then I turn off the chiller. Chiller usually includes a flow indicator that can be used by the Rudia to halt operations.
How does this vacuum switch work with the system, overall? I would think it would fault as the electronics are going to detect no coolant flow, if that’s how yours works?
I’m familiar with those type of switches. They are designed to use with a shop vac for dust collection. When the switch senses current flow on the main circuit, it passes power to the secondary circuit after a short delay, to prevent brownout. As long as the current is flowing on the main circuit, the secondary circuit continues. Once it no longer senses current flow on the main it shuts off current to the secondary circuit after a few secong delay, to prevent false short cycling and continued vacuum until the hose is clear.
From the wall. The two plugs are plugged into a heavy duty power strip that runs the laser cutter, chiller, fan, and powers my laptop. When I run my laser cutter, I don’t run anything else in my garage. It is connected to a 20amp outlet with 12 AWG and a 20 amp breaker.
I also don’t think this is a standard “chiller” as I dont think it uses refrigerant (I could be wrong) here is the link
The vacuum switch works by turning on the chiller once it reads that the laser cutter is turned on. Normally its meant to be used with a power tool. Like when you turn on a table saw it will turn on a shop vac to start sucking up the sawdust.
They claim the chillers detect not only flow, but over/under temperature and chiller failure, if you set the chillers controller up that way. On mine if I pinch the coolant hose, I get an error on the Ruida, so I’m sure it does flow.
You can see the schematic and how to wire it up in post 3. Mine is wired directly to the Ruida, which is how it’s designed to operate.
