Reading high can mean they are leaky. Not a big problem for decoupling caps, but suggests they are deteriorating.
The specs on electrolytic caps can be -20% to as high as +80%. I don't think that's a productive troubleshooting path. It seems everything connected to 12V got fried. The 12v is fixed but the collateral damage needs to be found.
@1audio
I can't find the right manual for the HTS-3500 MKII, so I'd like to verify my assumptions of its expected functionality wrt switching outlets.
(There's a manual for the HTS-3500, but not the MKII. The two differ significantly, the MKII having 2 switched outlets plus 2 switched-and-timed outlets on 2 separate circuits, vs the non-MKII's 4 switched outlets on one circuit).
Here are my assumptions:
Depressing the ON switch turns on the 4 switched outlets if they are in the OFF state, as follows:
- The 2 switched outlets turn ON immediately
- The 2 switched + timed outlets turn ON after a fixed, nonadjustable time delay (5 or 10 seconds?)
Depressing the OFF switch turns off all 4 switched outlets if they are ON:
- The 2 switched outlets turn OFF immediately
- The 2 switched + timed outlets turn OFF after the time delay
Is all of the above correct? Am I missing anything? Thanks!
I can't find the right manual for the HTS-3500 MKII, so I'd like to verify my assumptions of its expected functionality wrt switching outlets.
(There's a manual for the HTS-3500, but not the MKII. The two differ significantly, the MKII having 2 switched outlets plus 2 switched-and-timed outlets on 2 separate circuits, vs the non-MKII's 4 switched outlets on one circuit).
Here are my assumptions:
Depressing the ON switch turns on the 4 switched outlets if they are in the OFF state, as follows:
- The 2 switched outlets turn ON immediately
- The 2 switched + timed outlets turn ON after a fixed, nonadjustable time delay (5 or 10 seconds?)
Depressing the OFF switch turns off all 4 switched outlets if they are ON:
- The 2 switched outlets turn OFF immediately
- The 2 switched + timed outlets turn OFF after the time delay
- Depressing the ON switch when the outlets are already ON, or the OFF switch when the outlets are OFF, has no effect / does nothing
- Other than the aforementioned ON and OFF push-button switches on the right side of the front panel, the unit has NO main switch of any kind. In other words, the 6 UNswitched outlets are ALWAYS ON as long as the power cord is plugged into a live receptacle.
Is all of the above correct? Am I missing anything? Thanks!
Replaced HA17339 and all is well! (well, almost - the hum / buzz is still there).
The ON / OFF switches now operate as designed and the time delay works! Unless I'm missing something, this unit now works as it did when it left the factory. I left it on for a while, then checked for overheating components but couldn't find any.
As far as the buzzing noise - it comes out of inductors F2 and F3. They have some old shellac or varnish-like material on them that's completely dried out. Also, the buzzing only happens when the switched outlets are on. When they're off, it's silent. At this point part of me says good enough, time to put the unit back together.
Unless anyone thinks the buzzing could indicate a larger issue?
The ON / OFF switches now operate as designed and the time delay works! Unless I'm missing something, this unit now works as it did when it left the factory. I left it on for a while, then checked for overheating components but couldn't find any.
As far as the buzzing noise - it comes out of inductors F2 and F3. They have some old shellac or varnish-like material on them that's completely dried out. Also, the buzzing only happens when the switched outlets are on. When they're off, it's silent. At this point part of me says good enough, time to put the unit back together.
Unless anyone thinks the buzzing could indicate a larger issue?
A couple random thoughts:
- The unit had no ground when I got it. The pin was disconnected from the ground wire inside the plug. I fixed that early on and there is ground now, but I may still install a new plug.
- RLY1 and RLY2 control the switched outlets, but I don't understand what RLY3 does?
- Whatever happened to this unit that blew up PCB traces and fried half of the 12V section? The surge suppression board and MOVs look fine, which seems to rule out a massive surge. Unless of course the surge board was fixed or replaced. And the consensus seems to be that a load-side short couldn't have caused it. So what could it be?
In any event I'll take extra care during reassembly and I'll be watching for possible shorts to chassis etc.
- The unit had no ground when I got it. The pin was disconnected from the ground wire inside the plug. I fixed that early on and there is ground now, but I may still install a new plug.
- RLY1 and RLY2 control the switched outlets, but I don't understand what RLY3 does?
- Whatever happened to this unit that blew up PCB traces and fried half of the 12V section? The surge suppression board and MOVs look fine, which seems to rule out a massive surge. Unless of course the surge board was fixed or replaced. And the consensus seems to be that a load-side short couldn't have caused it. So what could it be?
In any event I'll take extra care during reassembly and I'll be watching for possible shorts to chassis etc.
I think there's one more thing to check to see if everything is working properly: the "remote" functionality.
I don't know if it's related, I also have a HTS5100 MKII and the cable with 12VDC 3.5mm plug accidentally pulled out of the socket when the unit was on, causing the HTS5100 to fail and my dealer replaced it with a new unit. That was many years ago and the unit had been in use for three weeks only.
Its possible that something came in the 12v that could damage stuff.
The inductors were known to buzz. Its "normal" if undesirable. Fresh potting probably won't help.
The inductors were known to buzz. Its "normal" if undesirable. Fresh potting probably won't help.
So only today you mention that it had no PE connection. It will not do what it is supposed to do without PE. At all. Something quite serious happened to that device and/or someone very incompetent tried to fix it. Many amateurs don't fully understand how PE is supposed to work. If it would be sold here one would assume it having been zapped in a 3 phase 400V situation. This may happen when the N connection is broken.
The left behind screw scenario after a first repair is still a possibility, it would also cause similar damage. I regularly see devices opened by guys that loose an M3 screw of the upper cover the moment they remove them. I have seen a left behind wrench left behind on one of the rails of a bare copper 3 phase busbar in a very high power system. When I asked the guy in charge if this was safe there was suddenly panic 🙂
As we can all conclude it was not protected itself and your version is IMHO not safe by design. Example: the sub 15VA transformer has a 15A fuse. Overcurrent won't be cut until 15A is reached. You could fry hamburgers on the cover and the fuse would still be intact. Solutions have been given in detail already. Don't believe reputations of designers and brands, trust on your simple findings per device per situation.
This inductors should not hum so I would clean them with something non aggressive and "paint" them with a thin coating of slow curing epoxy of the transformer potting kind and let it harden a few days without using the device. They should not make noise with light loads. The 120V system has of course high currents so it would be good to check what the load current exactly is. Fact is that these can be silent in normal use and normal circumstances so from about 30 cm. I build such devices and never hear a coil, the Belkin mains filters I tried out were also silent.
The left behind screw scenario after a first repair is still a possibility, it would also cause similar damage. I regularly see devices opened by guys that loose an M3 screw of the upper cover the moment they remove them. I have seen a left behind wrench left behind on one of the rails of a bare copper 3 phase busbar in a very high power system. When I asked the guy in charge if this was safe there was suddenly panic 🙂
As we can all conclude it was not protected itself and your version is IMHO not safe by design. Example: the sub 15VA transformer has a 15A fuse. Overcurrent won't be cut until 15A is reached. You could fry hamburgers on the cover and the fuse would still be intact. Solutions have been given in detail already. Don't believe reputations of designers and brands, trust on your simple findings per device per situation.
This inductors should not hum so I would clean them with something non aggressive and "paint" them with a thin coating of slow curing epoxy of the transformer potting kind and let it harden a few days without using the device. They should not make noise with light loads. The 120V system has of course high currents so it would be good to check what the load current exactly is. Fact is that these can be silent in normal use and normal circumstances so from about 30 cm. I build such devices and never hear a coil, the Belkin mains filters I tried out were also silent.
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Specialized potting compound would cost more than the unit. I do have clear silicone sealant and RTV lying around though. Would these be appropriate? We're not talking about potting transformers here.
Normally all dangerous and/or industrial stuff is way cheaper where you live. I could afford it here. 13 Euro for 290 grams. 2 Bottles. The bonus is that you can pot a few transformers too.
I know that you are not potting transformers. You have coils. You have coils that hum. You don't like hum. They hum mechanically because of AC currents, electromagnetic fields and famous dutchman Mr. Lorentz. There is a similarity with transformers. That is why I gave practical tips.
https://nl.wikipedia.org/wiki/Hendrik_Lorentz
https://en.wikipedia.org/wiki/Lorentz_force
Another one is not to use any silicone that contains acid. And another one is to not do that at all as currents will possibly cause heat that needs to be given to the environment. Measuring the coils temperature with the load you connect is a good idea I think. If temps are reasonable you could get away with 2 component glue applied to the side of the coils as an ongoing stripe with a syringe. The upper side must be able to give heat to the environment. I do the same with classic electro stuff when restoring those. It works.
Maybe my tips are worthless as reactions are short but reading back they seem to fit reasonably often 😀
I know that you are not potting transformers. You have coils. You have coils that hum. You don't like hum. They hum mechanically because of AC currents, electromagnetic fields and famous dutchman Mr. Lorentz. There is a similarity with transformers. That is why I gave practical tips.
https://nl.wikipedia.org/wiki/Hendrik_Lorentz
https://en.wikipedia.org/wiki/Lorentz_force
Another one is not to use any silicone that contains acid. And another one is to not do that at all as currents will possibly cause heat that needs to be given to the environment. Measuring the coils temperature with the load you connect is a good idea I think. If temps are reasonable you could get away with 2 component glue applied to the side of the coils as an ongoing stripe with a syringe. The upper side must be able to give heat to the environment. I do the same with classic electro stuff when restoring those. It works.
Maybe my tips are worthless as reactions are short but reading back they seem to fit reasonably often 😀
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Silicone is a thermal insulator so I was just going to run a single bead around the coils, not encase them in the stuff. Given silicone's excellent dampening properties that might do the trick.
Right now with a light load connected, the coils run approx 75-77 deg F (24-25 deg C) with ambient temperature in the low 70s.
Alternatively, some folks claim good results using either beeswax or hot-melt glue in old radios and such. Seems environmentally friendly.
I for one find your tips on point and valuable, Jean-Paul. They are very much appreciated.
Right now with a light load connected, the coils run approx 75-77 deg F (24-25 deg C) with ambient temperature in the low 70s.
Alternatively, some folks claim good results using either beeswax or hot-melt glue in old radios and such. Seems environmentally friendly.
I for one find your tips on point and valuable, Jean-Paul. They are very much appreciated.
Hot melt glue may work just as well.
Not too fond of it (it may become brittle) and one might not want to be a member of the “hot melt glue-iron wire-duct tape” gang 🙂
Not too fond of it (it may become brittle) and one might not want to be a member of the “hot melt glue-iron wire-duct tape” gang 🙂
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I think the design does keep it safe by using a class 2 transformer.
I believe RLY3 is for remote ON/OFF.
Put the unit back together and see if the buzzing noise still audible.
Here is a summary of the unit's behavior:
1. Unit is plugged into AC:
2. ON switch is depressed:
Switched outlets turn ON - "SWITCHED ON" LED turns ON
Switched & Timed outlets are OFF - "TIMED ON" LED is OFF
Voltmeter backlight turns ON
3. After ~7 seconds delay:
Switched outlets are ON - "SWITCHED ON" LED is ON
Switched & Timed outlets turn ON - "TIMED ON" LED turns ON
When OFF switch is depressed, sequence unfolds in reverse order, except that Switched & Timed outlets turn off first, then Switched outlets turn off after 7 seconds.
1. Unit is plugged into AC:
- Switched outlets are OFF - "SWITCHED ON" LED at left is OFF
- Switched & Timed outlets are OFF - "TIMED ON" LED is OFF
- Voltmeter shows AC voltage - dial backlight is OFF
2. ON switch is depressed:
Switched outlets turn ON - "SWITCHED ON" LED turns ON
Switched & Timed outlets are OFF - "TIMED ON" LED is OFF
Voltmeter backlight turns ON
3. After ~7 seconds delay:
Switched outlets are ON - "SWITCHED ON" LED is ON
Switched & Timed outlets turn ON - "TIMED ON" LED turns ON
When OFF switch is depressed, sequence unfolds in reverse order, except that Switched & Timed outlets turn off first, then Switched outlets turn off after 7 seconds.
I think you are correct. I tested the remote functionality with a 120V AC cable and it worked fine.
The buzzing can be heard from 8' away with the lid off, but with the lid back on I can't hear it from any farther than 12" or so. I'll leave the chokes alone. Good enough! 🙂
Thanks! I learned a lot in the process too, so thank you to everyone for your help, expert advice, and for keeping me on the right track. Hopefully this thread will someday help someone working on one of these units.
Yes. I'm searching for service info right now, especially a diag mode to activate discrete functions of the Philips CDM12. Coming up empty so far tho
WRT the extra relay- This patent will explain https://patents.google.com/patent/US6683770B1/en?inventor=richard+marsh&oq=richard+marsh&page=4 The idea is that any situation that will cause an MOV to overheat should disconnect the power. Later versions use active circuitery to operate the relay with a delayed reconnect to ensure stable power.
@1audio
Is it correct that these power conditioners are current-limiting, and to what extent?
I like to keep my gear plugged into the Monster because my wall outlets are too far otherwise. My current amp works just fine that way, but I am getting a pair of monoblocks rated 650W each on 120V, almost 3x more than my current amp. My question is whether the HTS-3500 MKII can handle this load gracefully.
Thanks!
Is it correct that these power conditioners are current-limiting, and to what extent?
I like to keep my gear plugged into the Monster because my wall outlets are too far otherwise. My current amp works just fine that way, but I am getting a pair of monoblocks rated 650W each on 120V, almost 3x more than my current amp. My question is whether the HTS-3500 MKII can handle this load gracefully.
Thanks!
It is true that they are current limiting in that they have a circuit breaker to meet UL and disconnect over 15+ A continuous. But in the (somewhat absurd) audiophile sense they are not. At one CES I demo'ed 4 large amps turning on and off repeatedly for the duration of the show. I had a scope connected to show the peak turn on current- 120A. No significant voltage sag associated with that. And the internal relays survived what was a life test. Typically house wiring would be the big limiter in current.
Sometimes what is percieved as current limiting is actually the effect of removing some of the line born noise and its modulation on the audio.
Sometimes what is percieved as current limiting is actually the effect of removing some of the line born noise and its modulation on the audio.