Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[dave w]

OK Dave,

I remember now that you're an "audio type".  Since I've never been shy of asking the stupid questions, can you explain what a "Bose - Cherudy filter" is? 

In the event that the explanation involves the use of Bessel functions, you can ignore the question.  I'd have to ask my math professor wife to explain them to me (again).  The explanation would start as "How can you not get this...".  There's a limit to the amount of humiliation I can take in one lifetime.

Boiler

You won't get a technical description from me, and I probably did not even spell correctly. I believe "Bose and Cherudy" are the mathematicians the filter was named after...which means your wife will know more about it than I. All I remember is it is a type of filter used in (either) a radio IF or a transmitter synthesizer. (Motorola  - 28 years) I confuse it with the Chebyshev filter. 

[tom j]

Say Boiler, you really seem to be up on this it's definitely above my pay grade but I have a dehumidifier average size by Westinghouse. Turned it on in the basement the other night and it put some noise in the system saw my All Lights On/Of getting a bit out of step. I don't use this very much except when the basement gets a little damp. Can't see a model number or anything. Any idea what the running amperage might be on a device like this? Saw those x10 Pro 5 amp filters for less then 4 bucks on EBay and would pickup a few if they would work on something like this. Thanks!

Tom j.

[Brian H]

The dehumidifier probably has a compressor in it for cooling. The starting current and maybe even the running current would probably be over the five amps. The coils in the five amp filters are not very heavy and maybe over loaded.

[dave w]

Say Boiler, you really seem to be up on this it's definitely above my pay grade but I have a dehumidifier average size by Westinghouse. Turned it on in the basement the other night and it put some noise in the system saw my All Lights On/Of getting a bit out of step. I don't use this very much except when the basement gets a little damp. Can't see a model number or anything. Any idea what the running amperage might be on a device like this? Saw those x10 Pro 5 amp filters for less then 4 bucks on EBay and would pickup a few if they would work on something like this. Thanks!

Tom j.

Average 40 pint a day humidifier is 500W - 700W. Soleus makes one with a scroll compressor that is < 300W (234W on my "Kill-A-Watt") however the compressor only lasts 32 days past the warranty expiration. Our new (sigh) Frigidaire 50 pint a day draws 558 watts on High.

As Brian said, a 5 amp filter might be a little tight unless your Westinghouse draws less than about 600W.

[Boiler]

Hi Tom,

As Brian and Dave have already pointed out, the XPPF filter is probably underrated for your dehumidifier.

The AF120 that you're using on your refrigerator should be more than capable of handling this load (15A).  As Jeff Volp pointed out, this may not be a true low pass filter.  On the positive side, it is working on your fridge which also uses a compressor (similar noise but probably lower current).

Can you move the AF120 to your dehumidifier as a test run?  If it doesn't work, I'd be hard pressed to recommend a different 10Amp or better filter for this application.

[tom j]

Say glad I asked! Maybe I'll try the The AF120 as you suggested, did someone say that because this is not a true low pass filter was really not designed to filter out noise from a appliance like a refrigerator, seems to work fine. Thanks

Tom j.

[tom j]

Say I was just wondering is there anyway I can determine what the running amperage is I have a Kill-A-Watt to and a multimeter. Thanks

Tom j.

[Brian H]

My Kill-A-Watt P4400 has an amperage read out choice.

[tom j]

My Kill-A-Watt P4400 has an amperage read out choice.

I actually have something similar let me check I think it does do amperage. Thanks


Tom j.

[Boiler]

Say glad I asked! Maybe I'll try the The AF120 as you suggested, did someone say that because this is not a true low pass filter was really not designed to filter out noise from a appliance like a refrigerator, seems to work fine. Thanks

Tom j.

Jeff Volp pointed out that this is not a true low pass filter.  Yes a true low pass would probably be better in this application.  The problem is, I don't know of any plug in LPF's in the 10 to 15amp range.  There are wire in units, but these are normally intended for protecting an entire circuit.

Since the AF120 is already working on your refrigerator, I'd give it a try on the dehumidifier.  The components in the two appliances are similar (compressor, pressure switches, etc) and the nose spectrum may be similar as well.

From your other post, if you are trying to measure the current draw of the Dehumidifier - don't forget to measure the start current.  Compressors can draw significantly more current on startup than they do at steady state speed.

 

[tom j]

Say glad I asked! Maybe I'll try the The AF120 as you suggested, did someone say that because this is not a true low pass filter was really not designed to filter out noise from a appliance like a refrigerator, seems to work fine. Thanks

Tom j.

Jeff Volp pointed out that this is not a true low pass filter.  Yes a true low pass would probably be better in this application.  The problem is, I don't know of any plug in LPF's in the 10 to 15amp range.  There are wire in units, but these are normally intended for protecting an entire circuit.

Since the AF120 is already working on your refrigerator, I'd give it a try on the dehumidifier.  The components in the two appliances are similar (compressor, pressure switches, etc) and the nose spectrum may be similar as well.

From your other post, if you are trying to measure the current draw of the Dehumidifier - don't forget to measure the start current.  Compressors can draw significantly more current on startup than they do at steady state speed.

 

Are you suggesting when you plug it in there's kind of like a surge so to speak? Seems like the running amperage is 4.6  is that to close to the 5 amp rating on the x10 Pro module. And the AF-120 appears to be working fine no more noise line problems. Just found the directions for this thing and it does have a max current so I'll have to check, got another question on this but I'll post later. Thanks!!

Tom j.

[tom j]

My Kill-A-Watt P4400 has an amperage read out choice.

Say Brian thanks!!!!! for reminding me about that amperage read out mine is similar to yours just made by UPM I think it also computes the dollar amount of the devices you're using if you input the charge per kilowatt hour. Say what's more important the running or start up and what would happen it it was exceeded. 

Tom j.

[dave w]

Are you suggesting when you plug it in there's kind of like a surge so to speak? Tom j.

Not when you plug it in, but when the dehumidifier starts there is a "starting current" which can be two to three times the "run current". Have you ever been in a home when the HVAC turned on and the lights flickered...thats starting current.  If the five amp filter is internally fused, the fuse will blow. If it is not fused then the risk is the compressor in the unit stalling because the filter wouldn't deliver the required "starting current".

[tom j]

 

Are you suggesting when you plug it in there's kind of like a surge so to speak? Tom j.

Not when you plug it in, but when the dehumidifier starts there is a "starting current" which can be two to three times the "run current". Have you ever been in a home when the HVAC turned on and the lights flickered...thats starting current.  If the five amp filter is internally fused, the fuse will blow. If it is not fused then the risk is the compressor in the unit stalling because the filter wouldn't deliver the required "starting current".

Thanks Dave! I've learned a lot!  Just a few more things my Frig is rated at 15 amps and has a running current of 12 so does that mean that it won't exceed 15 amps? And is there any way my AF120 can damage my refrigerator, it's not new but I wouldn't want to damage the compressor or something. Thanks again Really!!!!

Tom j.

[Brian H]

The fuse in the AF120 is a time delay type. It is meant for momentary surges from motors etc. starting. I would also say the components in the filter are picked to accommodate momentary over currents. Just that a constant over current could damage them.

The Smarthome FilterLincs; both 10 and 5 amp filters. Have a soldered in time delay fuse.

The 5 amp X10 and X10Pro filters have no fuses and a constant overload can overheat the coils.