how good is the Dylos DC1100 particle counter?
These particle counters are aimed at home owners:
It has two readings, one for "small particles" > 1 um and another for "large particles" ("from approximately 5um and up"). It's obviously too coarse for professionals, but it might be useful for a home owner wondering what makes a difference. I just wonder about its reliability and durability; will it stop working after a year? Two? Five? Will it produce wildly variable counts, or reproducible ones? Has anyone used it? Does it have annoying quirks or notable weaknesses?
Last edited by pmeunier; 10-02-2007 at 06:55 PM.
Ya get what ya pay for. Looks like a gimmick to me.
Dylos DC1100 is no gimmick!
I am the designer of the DC1100 so I don't claim to be impartial, but this instrument is no gimmick - it is a true laser particle counter! I spent 13 years designing particle counters for clean room use which cost from 8 to 16 thousand dollars. I targeted the DC1100 primarily at the home user who wants to know their indoor air quality and when it is time to change filters, turn on their purifiers, etc. However, HVAC professionals are also finding it useful as a tool. Not only for their own diagnosis, but to demonstrate to their customers the effectiveness of their work. Some also leave it in homes to gather data for review during follow up visits.
To address some of your concerns ...
As for reliability - we've only been marketing this product for about a month and haven't had any fail yet. The main problem with laser particle counters is the laser dying. Lasers just do that over time. I've done accellerated life tests for several months without failure so I would expect the laser to last for years. In any case, our repair charges are easy on the wallet - $35 flat fee. Remember, your $4500 Fluke will also need annual calibrations which will run hundreds of dollars.
The 1um lower detection range - we felt this was adequate for the home user, but HVAC professionals are more demanding. We have units with 0.5um detection limits for a small additional charge upon request. We just didn't feel the home owner would care enough to pay extra.
I am not saying the DC1100 is a better tool than the Fluke. The Fluke has a lower detection limit, is more rugged, and is battery operated (the DC1100 must plug in). But for many uses it will work just as well for a tiny fraction of the cost. The DC1100 actually is better in some ways as it has large bright numbers on the display which the contractor and the client can easily view while the unit is sitting on the table. The DC1100 also stores data so you can go back and look at the daily averages over an entire month or hourly averages over the past day, etc.
The DC1100 is no gimmick, it's the real deal!
Very interesting, thanks. I'll want the 0.5um detection limit, that was bothering me a little. I think I'll order one the next time I'll indulge myself. Heck it's cheaper than a vacation trip and I'll probably have more fun with it than dealing with air travel and hotels. (and the allergies due to their carpets and general lack of dehumidification )
Who dies with the most toys wins?
Seriously, I think it will help me to know for sure if the filters I have are doing their job, if the tinkering I do helps any, and whether I should stay indoors or if it's a good time to go for a walk.
lpc_engineer, please understand the most of us have seen things advertised for a very low price that fail to meet our expectations when used. Your product may be fine but I am always skeptical when I see extremely low prices. From a professional point I am always interested in accuracy. What is the accuracy of this unit. If it is fairly reliable I could see using one to log data at a customers house where you would not want to leave your Fluke unattended.
pmeunier. When you get your unit please post a review.
pmneunier, thank you for your comments. The DC1100 will do all those things you mentioned.
mbarson, accuracy is not normally specified for particle counters as it would be for say a volt meter. It is not unusual to see two $8000 particle counters disagreeing by 30% or so, especially from different manufacturers. A major reason for this is that units are calibrated with standard particles which are uniform, round, plastic spheres, but in the real world they measure irregular shaped chunks of whatever happens to be floating in the air. There is a JIS calibration standard, but it does not eliminate these issues. Fluke claims to do a calibration which at least partially adheres to JIS. I don't know what Fluke charges, but I'd say $450 is in the ballpark for this kind of cal. To keep the price of the DC1100 down to $149 I must use a proprietary calibration method. Overall the results are good and the readings on my units will pretty much track the Fluke or other counter's readings.
It never ceases to amaze me about the people who participate in this site.
I received a mailing on your device and was skeptical and tossed it. After reading your posts I would like to take another look at it.
Please contact us through our website.
Let's say I managed to get very low counts somehow, perhaps by having a good HEPA filter running on the highest speed in a closed room. Almost every instrument gives a background noise count even when there's nothing to detect. In a situation where the count is low, that background noise count becomes significant. With your unit, is it possible to estimate or measure that background noise count so that I can subtract it from the readings?
The DC1100 reads out in particles per cubic foot divided by 100. So, if the DC1100 reads "1" that means there are 100 particles per cubic foot. You can easily get the DC1100 to zero count by putting filter material directly over the air inlet and sealing the edges with tape. By the way, those spurious counts you are asking about are sometimes called "dark counts" in the industry. Some particle counter manufacturers simply subtract off so many counts per minute to correct for this. The DC1100 by virtue of its design does not need any dark count correction. So, if you wait long enough you may be able to get the counts down to zero in a closed room. One of my customers actually tried this successfully, but as soon as any movement occurred in the room counts started registering. A well-filtered room might read 20 or so when the outside ambient reads 500. Another customer who was using very aggressive filtering and even some very basic clean room construction techniques was able to get consistent readings below 10.
What is the particale size range ? Might be intrested if its 2.5 -.01
The Dylos DC1100 gives 2 readings .... small particles ( 1 micron and up) and large particles (5 microns and up). The readings are given as concentrations of particles/.01 cubic foot. That is, a reading of 2 means 200 particles per cubic foot. We also can calibrate for 0.5 micron instead of 1 micron - just ask, it's an additional $50.
So what's the deal on the lifespan of the laser?
Is it the number of hours it's actually in use, or is the time it's not in use also a factor?
Generally a laser diode will slowly degrade while it is on. Its shelf life while off is usually much longer. Higher temperatures and output power of the laser accelerate this process. Diode lasers have tiny mirrors on their ends and the degradation of these mirrors is a major failure mode. As the laser ages it will draw more current to keep its power output up until it finally burns itself out. The laser on the DC1100 is relatively low power and has performed well in life tests so I predict a long life. It can also be placed into "monitor mode" where it will sample periodically, turning the laser off between samples, which would further extend the life.