View Full Version : Quick Fog Machine Question

09-01-2010, 08:49 PM
I want to set up a small Halloween display this year and I have a question about small fog machines. I don't need anything that really clouds up the place, but want something to pump out enough to see the effect. I don't want to spend a fortune, and I think I need about 3 of them.

If someone has some cost effective options, let me know.

Here's the real question(s). Do these things need to warm up or once power flows will the fog billow? Do I need any special setup or can I just plug into a Renard 24, SS series, etc?

09-01-2010, 09:25 PM
The fog machine needs to be plugged in and left on to keep the fog chamber hot. The smoke is controlled by a small pump that squirts the fog juice into the smoke chamber. If you want to control the smoke output via vixen, you want to use a relay to turn the pump on/off. You could use a AC or DC renard device to control the pump, by using an appropriate relay - i.e. a 120 volt AC relay for a renard SS series or a DC relay for a 24 LV.

The smoke machine most likely has what looks like a female, three connector plug on it for a remote control. I would need to research some, but this is the connection that you need to wire up to your relay to turn the pump on/off.

The smoke will not stay on constantly. There is a temperature sensor in the smoke chamber that will turn the pump off when the smoke changer temperature drops below a pre-set value. The pump will remain off until the required temperature is reached in the chamber.

But you should be able to reliably create controlled bursts of smoke controlled by vixen, as long as the chamber stays hot enough to have the pump enabled when your remote control relay closes.

Just a quick edit - I would not recommend running the main/heater 120 AC power through a renard. I don't have my smoke machines in reach right now, but they probably draw too much power for this...

09-01-2010, 09:27 PM
They do need to warm up, it will usually take about 3 to 5 minutes. They will not work if directly plugged in to a controller, but can be controlled though the trigger button which controls the fog, usually a button on top of the machine or on a remote . You will need to remove the button and connect the two wires to a relay or SSR board. Make sure the relay/triacs can handle the amps though.

Hope this helps.

09-01-2010, 09:32 PM
You might want do some searching through the forum - pretty sure this has come up before a few times. I think it involves installing a relay on top of the remote control switch and ensuring you have a snubber on the controller end.

09-01-2010, 09:33 PM
All of the fog machines I have seen do not put out continuous fox except for the VEI.

I have two Chauvets- a F1700 and a F1250. THey both work well, but neither is continuous. You can get a DMX adapter and control them via DMX.

If this is indoors you could use smaller machines. Outdoors you really need the 1700.

09-01-2010, 09:55 PM
First off, I would not suggest even consider plugging a fog machine into a Renard board. I've owned 5 of them to date and the smallest one draws over 5 amps when heating and pumping - not something the Renard series was designed to handle. Now, if you want to wire up a relay to it that trips the "fog switch" (as suggested), that's something else.

In the past years, I've used multiple small-medium sized fog machines in my Halloween display. I hated having to wait for them to reheat so often (really, it's like you get 30 seconds of fog, then have to wait 5 minutes for it to reheat). Last year, I decided to be bold and get a slightly higher-end Chauvet hurricane 1300, pretty much the cheapest one I could find that does continuous fog and doesn't look like it'll self-destruct. I put it side-by-side in my garage with one of my small ones to do a comparison, and well, before my small one fully heated up my garage was filled with so much fog I could no longer see more than three feet. In the end, I would suggest, if possible in your scenario, to get a larger one that does continuous fogging and look into the option of "piping" some of the fog around using PVC and small fans inline with it. That worked a lot better for me than having 3 small machines in various locations and I got fog when I wanted it, not when my machine decided it's hot enough.

09-02-2010, 01:28 AM
Another tip for fogging - run the fog through a chiller, and it'll hang low to the ground. A DIY chiller is pretty simple to make.

09-02-2010, 03:57 PM
I would love to do this, but probably won't have the time this year as it seems involved. I love the chiller and low hanging fog concept though. I bet that is really cool looking.

Thanks for the info. I'll store it for later use. Just blinky flashy for Halloween this year!