New Woodshop Construction #6: Hacking the Delta 50-875 Air Cleaner

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Blog entry by Patrick Jaromin posted 03-06-2008 02:08 PM 20974 reads 3 times favorited 13 comments Add to Favorites Watch
« Part 5: Custom Collector Controller Part 6 of New Woodshop Construction series Part 7: An Hour Here, a Half-Hour There and a Few Saturday Mornings »

(This post is based on a forum thread.)

After completing my dust collection system installation, I turned to my air cleaner, the Delta 50-875. I had decided to install it just above my table saw—about 2/3rd’s of the way along the wall, where the intake would be in line with the front door and the outfeed inline with the ceiling mounted vent fan. After reading “Woodshop Dust Control” this seemed like the ideal placement and this location had the added benefit of not obscuring any usable wall space—which is at a premium in my small shop.


An Awkward Arrangement

One of the selling points of this unit is the built-in infrared remote control that allows you to install it out of reach and control it from below. The problem is that the remote sensor is in the back of the unit. While the unit location is ideal for air flow, it’s rather awkward for IR control as I’d need to walk around to the back of the unit, and to a “far” corner of the shop, to turn it on/off. I’ve always thought that what I really wanted to do was to control it with a switched outlet. The problem with that scenario is that the control panel built into the unit is solid state and doesn’t “remember” the settings when you unplug the unit. That is, if you turn it on and then switch off the outlet it’s plugged into, when you switch the outlet back on, the air cleaner will remain “off” until you again manually press the “on” key on the unit or the remote control.

So, there was no way to make this happen…or was there? I reasoned that since it’s just an electric motor and a control panel, certainly there would be a way to re-wire the unit, bypassing the built-in solid-state controls so that I could hook to a switched outlet.



The air cleaner itself is pretty basic. It’s a rectangular metal box with a blower motor/fan in a housing, and a control panel. The motor and control panel are both mounted on the back panel which is simply screwed into the metal box. Once the backpanel assembly, including the blower was removed, I began the process of working out exactly what needed to be done to re-wire the motor. Fortunately, the motor wiring connects to wires from the controller through a nylon connector that, once unplugged provided an easy means of measuring various voltages and resistance. As I knew nothing about wiring AC motors, I began the process with a google search…many of them. Unfortunately, none provided me with anything that I could really use to definitively determine how this motor worked. In fact, I was left with more questions than I’d had originally…who knew there were so many types of AC motors! Initially, as there were 3 colored wires (Red, Blue and Black) and one White (clearly “common”), I assumed there were 3 windings and each color represented one of the 3 speeds that the unit boasts. Based on what I’d read, however, I was now concerned that the large-ish capacitor on the red wire indicated that I might have a “capacitor start” motor which would require something more complicated than simply applying voltage to one of the wires. Perhaps an electrical engineer, at this point, would have provided me a definitive way to check this out…but there weren’t any in my shop, so I tried a different tack.

I reasoned that the best way to reverse engineer this setup was to hook up each of the colored wires in turn to my volt meter—using white for common—and turn the unit on, cycle through the various speed settings and note the voltages. This did the trick. Here are the measured results:

wire slow medium fast
RED 121V 9V 9V
BLUE 9V 121V 9V
BLACK 14V 14V 121V

Clearly this was going to be as straight-forward as I had first hoped! Red = slow, blue = medium and black = fast. That’s all there was to it!

Let the hacking begin…


Now I was ready to start. In thinking through exactly how I wanted to wire this up, I realized that I might want to have the ability to change the speed at some point without opening the unit up. I also figured it would be pretty simple to install a switch that would basically allow me to “undo” this hack and use the unit as nature, and the Chinese factory had intended without having to un-hang and re-open the unit. The solution was a couple toggle switches. Since there’s an Ace hardware store right up the street from my office, I decided to stop by at lunch and see what they had. I was looking for a SP3T rotary switch that would allow me to cycle through all three speeds—but the only one they had was rated at 4A max. The fuse mounted in the control panel is rated at 5A, so I figured this switch wouldn’t do. The next closest was a SPDT switch, center off—and two speeds seemed “close enough.” For the “hack bypass” switch, I got a DPDT. While it seemed like it should be sufficient to switch only the “hot” wire, since I was going to essentially be supplying power to the output of the controller when using the hack (see drawing), I was concerned that a closed common connection might allow a circuit to complete and result in “who knows what”(tm) happening. So, I decided the safest thing to do would be to simply switch both common and hot.

The plan

Here’s a basic drawing of what was done:

50-875 hack

Moving forward

So the whole point of this modification was to allow me to control the unit by a switched outlet. The switched outlet is managed by an Insteon SwitchLinc which will allow for event-driven activation, such as turning on and off automatically with tools and/or the dust collection unit and wireless RF remote control via an X10 keychain remote. I’ll be refining the programming over the coming weeks/months.



(originally posted at

-- Patrick, Chicago, IL

13 comments so far

View Grant Davis's profile

Grant Davis

787 posts in 4142 days

#1 posted 03-06-2008 02:56 PM

Very nice write up on the conversion you made. I want to say that your shop is an inspiration and I look forward to your blog postings about it.

-- Grant...."GO BUCKEYES"

View Patrick Jaromin's profile

Patrick Jaromin

406 posts in 4066 days

#2 posted 03-06-2008 03:38 PM

Thanks, Grant! Nice to know it’s appreciated by someone. In the “real world” my non-woodworker friends tend to stare at me blankly when I ramble on about this stuff! :)

-- Patrick, Chicago, IL

View teenagewoodworker's profile


2727 posts in 4002 days

#3 posted 03-06-2008 05:16 PM

wow. you’ve got yourself a great dust collection and air purification system there. after all this is done you’re gonna have the cleanest shop on Lumberjocks.

View DaveH's profile


400 posts in 4012 days

#4 posted 03-06-2008 05:33 PM

Thanks for the post. I’m going to be making the same modification.

-- DaveH - Boise, Idaho - “How hard can it be? It's only wood!”

View Tom Adamski's profile

Tom Adamski

306 posts in 4004 days

#5 posted 03-06-2008 06:04 PM

I knew I should have taken an electronics class…

-- Anybody can become a woodworker, but only a Craftsman can hide his mistakes.

View Patrick Jaromin's profile

Patrick Jaromin

406 posts in 4066 days

#6 posted 03-06-2008 08:24 PM

taw- Not sure about the “cleanest” but I’m aiming to be at least among the “healthiest.”

Dave- keep me posted!

Tom – Why? I didn’t. ;)

-- Patrick, Chicago, IL

View northwoodsman's profile


245 posts in 3980 days

#7 posted 03-07-2008 01:33 AM

Interesting. I have a Jet model that has a very similar control panel. The remote works from almost anywhere in my shop.

-- NorthWoodsMan

View John Gray's profile

John Gray

2370 posts in 4119 days

#8 posted 03-07-2008 06:05 AM

Strangely enought the air filter looks just the same as my Grizzly G0572 Hanging Air Filter w/ Remote, and I really like it.

-- Only the Shadow knows....................

View Patrick Jaromin's profile

Patrick Jaromin

406 posts in 4066 days

#9 posted 03-07-2008 03:53 PM

NorthWoodsMan- You’re clearly luckier than I. The infrared remote with the Delta (looks like an identical control panel) in my shop, in both my “old” shop (garage) and my “new” shop I had to stand pretty much directly behind the thing in order for the remote control to function. It was a major pain. Now I have an X10 RF remote that works from anywhere.


That said, the remote is just a “bonus” as my other issue with the Delta remote is the fact that it would occasionally run away and hide from me…I’m really more interested in controlling it via my keypads located at both entrances and also programming it to turn on/off automatically (after a delay) with the dust collection system. Neither of these would work with the unit “as is”.

-- Patrick, Chicago, IL

View Dadoo's profile


1789 posts in 4224 days

#10 posted 03-08-2008 04:35 AM

I was thinking of moving the IR sensor to the other side of the case, but after looking up your schematic ( I see the IR sensor must be integral to the circuit card. I’ve also overcome some IR sensors (VCR,etc.) by using a small mirror to reflect the IR light or by using fiber optic cableing.

Interesting modification you have made. Does it work to your satisfaction now? How’s this unit for dust removal?

-- Bob Vila would be so proud of you!

View Patrick Jaromin's profile

Patrick Jaromin

406 posts in 4066 days

#11 posted 03-08-2008 05:41 AM

Dadoo: I’m very satisfied with both the modification and the unit. I can’t say whether or not this one is any better/worse than the others, but it suits my needs just fine.

Tonight I setup an event in the software (HouseLinc) that controls the outlet the modified cleaner is hooked up to. So now, when I turn on my dust collector, the cleaner automatically starts up. When I turn the dust collector off, the unit continues to run for an additional 2 minutes before turning off. I’ve chosen the delay arbitrarily—and it’s not enough time to completely turn over the air in the shop (need between 5 and 10 minutes for that) so I may change it, but it does mean that I’ll be running the air cleaner far more often than I did before.

And yes, the IR sensor is integrated…however I would imagine it wouldn’t be too difficult to remove the control panel and solder on a new and/or additional sensor with improved placement. As you can see in the pics, the PCB is accessible without unmounting it from the unit, so provided you could locate the sensor’s connection points to the board, I would think it would be pretty straightforward and not require too much mucking about. Obviously this would be quite a bit riskier than my mod.

-- Patrick, Chicago, IL

View Dadoo's profile


1789 posts in 4224 days

#12 posted 03-08-2008 05:00 PM

You’ve really touched my “geek” side with this House-Link device. My wife won’t be too happy with that fact, but since you live in Illinois, you should be safe! LOL!

I really like your finished pine walls too. Gives the shop a warm feeling. I’m thinking of finishing mine as well and have been contemplating doing the same. I think that project though is way down the road. Just too much else to do right now.

When you’re finished you’ll have to contact Doug Bordner for a LumberJock shop tour.

-- Bob Vila would be so proud of you!

View ELB's profile


11 posts in 967 days

#13 posted 06-07-2016 01:57 PM

Ha! How ironic that I found this (very old) thread.
My Delta air filter let the smoke out of it’s control board (which is now a discontinued part), so I removed the control board and replaced it with 3 relays and a Raspberry Pi. Now I turn my air filter on/off by accessing a web site (via my phone) hosted on the Raspberry Pi control board. 3 relays + raspberry pi = ~$40. :)

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