Clothes Dryer Moisture Sensor

snipped-for-privacy@ipal.net wrote:


More proof that you are a pathetic troll. Are you related to the nutball 'Phil' from dowen under?
--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 03 Mar 2008 14:49:37 -0500 Michael A. Terrell
| snipped-for-privacy@ipal.net wrote: |> |> On Mon, 03 Mar 2008 10:27:10 -0500 Michael A. Terrell
|> |> |> |> On Sun, 02 Mar 2008 22:12:13 -0500 Michael A. Terrell
|> |> |> |> |> They don't CLAIM to provide such protection. So no, I cannot list a mode |> |> |> that CLAIMS this. They just HAPPEN to do so because of the fact that the |> |> |> MOV breakdown voltage is relatively low. So ultimately, it is your trick |> |> |> question that is the troll. |> |> | |> |> | |> |> | Typical troll bullshit. |> |> |> |> This from someone that never directly addresses the technical issues when |> |> it is so much easier to just make a personal attack. |> | |> | |> | What do you call your post other than an attack? |> |> A defense. | | | More proof that you are a pathetic troll. Are you related to the | nutball 'Phil' from dowen under?
My ham call doesn't begin with VK. Or have you not noticed it.
--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@ipal.net wrote:

Whoosh!!!!!!!!!!!!!!! You don't have to live in the same country, or even on the same continent to be spawned from the same defective DNA.
--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

If you really want to protect your equipment you should have a very fast operating fuse, selected for ~125% of the FLA of your equipment in front of the MOV. Then while the MOV is self destructing the fuse will blow
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@ipal.net wrote:

. Damage to a TV obviously depends on the TV and the overvoltage.
The IEEE guide goes on a length how the protected load can be connected across the MOVs or connected to the incoming line. If connected across the MOVs, the protected load will be disconnected when overheating MOVs are disconnected on failure. I suspect that MOVs will overheat and be disconnected before high current operates overcurrent devices. A few plug-in suppressors will disconnect on overvoltage. .

. The intended point was that MOVs dont normally fail by "open[ing] back up". .

. MOVs, like anything else, will fail. The normal way they fail is low resistance .

. It isnt a design. It is the way they work. .

. Why would you think UL isnt testing for safety risks.
--
bud--

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
| snipped-for-privacy@ipal.net wrote:
|> |> | Martzloff has also written "In fact, the major cause of TVSS [surge |> | suppressor] failures is a temporary overvoltage, rather than an |> | unusually large surge." |> |> And these would not damage the TV? | . | Damage to a TV obviously depends on the TV and the overvoltage. | | The IEEE guide goes on a length how the protected load can be connected | across the MOVs or connected to the incoming line. If connected across | the MOVs, the protected load will be disconnected when overheating MOVs | are disconnected on failure. I suspect that MOVs will overheat and be | disconnected before high current operates overcurrent devices. | A few plug-in suppressors will disconnect on overvoltage.
And you are saying what?
|> |> If that voltage is what the UL says is right, and tests for (I presume |> |> they have surge simulation tests under power to verify that MOV devices |> |> don't just open back up under a surge event, etc) |> | . |> | UL1449 has quite a few tests. MOVs fail by conducting. |> |> Conducting when the voltage reaches the specified level is doing the job |> expected of them. | . | The intended point was that MOVs don?t normally fail by "open[ing] back up". | . |> I would not call that a failure. | . | MOVs, like anything else, will fail. The normal way they fail is low | resistance
In they sense they no longer provide protection, that is a failure.
|> The device may not |> be usable after that event (the MOV being fused to conduct), but that is |> part of the design. | . | It isn?t a design. It is the way they work.
The design of the surge protector is to use the characteristic of the MOVs.
|> I believe UL should be testing surge protectors with respect to things |> like whether they pose safety risks. Will it electrocute me when I flip |> the switch on it? Will it break and short out when I try to plug in to |> one of its outlets? Will the cord on it fail and expose wires when it is |> handled a little roughly? Will it develop a hot spot and result in my |> house burning down when I am away or asleep? Will it explode when given |> the design voltage plus or minus the prescribed margin range? | . | Why would you think UL isn?t testing for safety risks.
I didn't say they aren't. I'm commenting about the expectations as a response to a comment about what I thought were poor expectations.
--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Feb 27, 1:02 pm, snipped-for-privacy@ipal.net wrote:

Electronic power supply must withstand 300 volts for 3 milliseconds without damage and repeatedly - an industry standard. Appliances typically do better. If suffering usually long surges of the type suspected, then dimmer switches and GFCIs throughout the building are being replaced routinely. Changing incandescent lamp intensities elsewhere would be an obvious symptom. However, if a suspected surge is a different type (the typically destructive type); then damage, what those voltages are between, and a solution are different.
As usual, best evidence is the dead body. What on that electronics failed would say so much about why.
A 'whole house' protector for 240 volts (North American) means everything (including 120 volt appliances) has protection; if that protector also has an essential and short earthing connection. If electronics damage still occurs, then surges do not explain the failure.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
w_tom wrote:

. An IEEE guide on surges and surge protection at: http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.pdf has an illustration of a surge coming in on a cable service (pdf page 40). The problem is the ground wire from cable entry block to power service is too long allowing a damaging voltage between cable and power wires. A power service suppressor would do nothing to solve the problem.
Cable, phone, ... other entry protectors need to protect to ground and have short ground wires to the earth conductor at the power service. Otherwise the guide says "the only effective way of protecting the equipment is to use a multiport [plug-in] protector". A N-G bond in the power service also helps limit the voltage difference, particularly if a power service surge suppressor is not used.
A guide on surges from the US-NIST cites US insurance information that indicates equipment most likely to be damaged by lightning is computers with modem connection and TV related equipment - presumably with cable connection. All can be damaged by voltage between signal and power wires.
--
bud--

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
| http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.pdf | has an illustration of a surge coming in on a cable service (pdf page | 40). The problem is the ?ground? wire from cable entry block to power | service is too long allowing a damaging voltage between cable and power | wires. A power service suppressor would do nothing to solve the problem. | | Cable, phone, ... other entry protectors need to protect to ground and | have short ?ground? wires to the earth conductor at the power service. | Otherwise the guide says "the only effective way of protecting the | equipment is to use a multiport [plug-in] protector". A N-G bond in the | power service also helps limit the voltage difference, particularly if a | power service surge suppressor is not used.
If you do not have the proper common entrance for all services in one place, then the effectiveness of the surge protector power strip will be reduced. It's still better to have one than not. But it is no replacement for having the correct entry protection, which includes cable, phone, and power coming in at the same location and grounded together so voltage differences between these types of wiring are eliminated (at least with respect to surges coming in from outside on the wire).
| A guide on surges from the US-NIST cites US insurance information that | indicates equipment most likely to be damaged by lightning is computers | with modem connection and TV related equipment - presumably with cable | connection. All can be damaged by voltage between signal and power wires.
The differential voltage is the most common event, so this is certainly the issue most needed to be addressed.
--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@ipal.net wrote:

. A lot of houses have signal entrances too distant from power services. It is better to have a good "single point ground". But everything I have read indicates multiport plug-in suppressors with high ratings will provide protection for almost everything but a direct lightning strike to a house. The IEEE guide has an illustration of a multiport suppressor protecting when a cable entry is too far from the power service. The impedance to surges of the wiring inside the house greatly limits the current, and hence energy, available at a plug-in suppressor.
--
bud--

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
| snipped-for-privacy@ipal.net wrote:
|> |> | http://www.mikeholt.com/files/PDF/LightningGuide_FINALpublishedversion_May051.pdf |> | has an illustration of a surge coming in on a cable service (pdf page |> | 40). The problem is the 'ground' wire from cable entry block to power |> | service is too long allowing a damaging voltage between cable and power |> | wires. A power service suppressor would do nothing to solve the problem. |> | |> | Cable, phone, ... other entry protectors need to protect to ground and |> | have short 'ground' wires to the earth conductor at the power service. |> | Otherwise the guide says "the only effective way of protecting the |> | equipment is to use a multiport [plug-in] protector". A N-G bond in the |> | power service also helps limit the voltage difference, particularly if a |> | power service surge suppressor is not used. |> |> If you do not have the proper common entrance for all services in one place, |> then the effectiveness of the surge protector power strip will be reduced. |> It's still better to have one than not. But it is no replacement for having |> the correct entry protection, which includes cable, phone, and power coming |> in at the same location and grounded together so voltage differences between |> these types of wiring are eliminated (at least with respect to surges coming |> in from outside on the wire). | . | A lot of houses have signal entrances too distant from power services. | It is better to have a good "single point ground". But everything I have | read indicates multiport plug-in suppressors with high ratings will | provide protection for almost everything but a direct lightning strike
Maybe almost. Definitely not all.
| to a house. The IEEE guide has an illustration of a multiport suppressor | protecting when a cable entry is too far from the power service. The | impedance to surges of the wiring inside the house greatly limits the | current, and hence energy, available at a plug-in suppressor.
Tell that (impedance of inside wiring) to some past devices I've had destroyed by lightning induced surges, or direct hits.
--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@ipal.net wrote:

If you are talking about a direct lightning strike to a building, I specifically exclude them above. Protection includes lightning rods. If you have a tower antenna you are talking about a whole different level of protection.
If you are talking about general electronic "devices", the branch circuit impedance does not limit the voltage (although US panels and receptacles will arc over at about 6kV).
For plug-in suppressors, the suppressor clamps the voltage and the branch circuit impedance greatly limits the current.
--
bud--

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
|> Tell that (impedance of inside wiring) to some past devices I've had |> destroyed by lightning induced surges, or direct hits. |> | If you are talking about a direct lightning strike to a building, I | specifically exclude them above. Protection includes lightning rods. If | you have a tower antenna you are talking about a whole different level | of protection.
I was talking about either direct strike or an induced strike on any of the incoming service lines.
| If you are talking about general electronic "devices", the branch | circuit impedance does not limit the voltage (although US panels and | receptacles will arc over at about 6kV). | | For plug-in suppressors, the suppressor clamps the voltage and the | branch circuit impedance greatly limits the current.
... until the breaker can trip and open the circuit if the voltage is not as high as the arc-over level.
--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Lightning striking utility wires down the street may be a direct strike to appliances inside a building. We install protectors to make direct lightning strikes irrelevant. 'Whole house' protectors are sized and earthed so that direct lightning strikes do not find earth ground, destructively, via household appliances. This is how protection was implemented even 100 years ago.
Lightning view utility's AC electric wires as an antenna connected to household appliances. What was proven in radio stations also applies to protecting household appliances. Protection proven 100 years ago for radio station antennas and telephone company facilities is also provided by a properly earthed 'whole house' protector. Only plug-in protectors don't do what has been proven effective for over 100 years.
Type of surge that typically overwhelms protection already inside all appliances is the direct lightning strike. We install a 'whole house' protector to make direct lightning strikes. Bud does not recommend plug-in protectors for the type of surge that typically does damage? What kind of protection is that? Profitable. Ineffective. Does not remain functional after a typically destructive surge. Appliances can be damaged by a direct lightning strike if lightning to AC utility wires is not earthed. We earth an effective protector for direct lightning strikes. We install plug-in protectors to maximized profits.
Discussion about effective protection is about making the direct lightning strike irrelevant - so that the protector even remains functional. 'Whole house' protectors earth direct lightning strikes AND remain functional. Bud admits that plug-in protectors do not do what is necessary for effective protection.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
w_tom wrote:

. w_ apparently believes a strike to a utility line down the street with multiple paths to ground, a distant connection and coming through controlled entrance to a house is the same as a strike to an adjacent tower antenna sticking far above anything else and connected to sensitive electronics in the house. .

. UL listed suppressors have MOVs from H-G, N-G, H-N. That is all combinations and all possible surge modes. w_ has never explained how a common mode surge coming in on a power service gets past the N-G bond required at all US services. Past the service the surge is transverse mode. .

. Direct lightning strike is direct strike to a building in the beginning quote. Apparently w_ thinks that a service panel suppressor provides that protection, without lightning rods. w_ lives in a fantasy world. .

. I admit they do not protect against a direct lightning strike to a building. What a radical idea.
--
bud--

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
| UL listed suppressors have MOVs from H-G, N-G, H-N. That is all | combinations and all possible surge modes. w_ has never explained how a | common mode surge coming in on a power service gets past the N-G bond | required at all US services. Past the service the surge is transverse mode.
The surge does not pick a specific direction to take when it comes to a fork in the path. The N-G bond is such a fork. The two paths of the fork are 1: go over to G ... 2: continue with N. What it really does is take both paths. So now you have less surge going past the N, but some does. The part of the surge on H is still at full strength because there is no H-G bond. Now is it partially common mode (at the level of N) and partially differential mode (at the level of H minus N).
What will help to make sure more of the surge goes via G instead of staying on N is to ensure that G has the lowest _characteristic_ impedance right at the point of the bond. That means things like less inductance and less skin effect. An increase of impedance on the continue-N path could also help. Then you get more than half of the surge going over G instead of N. Maybe you can get a lot.
Fortunately, as N continues on, there is a lot more impedance in the form of inductance at the high frequency leading edge of the surge. But the closer the start of that higher impedance is to the N-G bond, the more that can be reflected back to go down the N-G bond.
--
|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@ipal.net wrote:

. The panel 'ground' and neutral are bonded. They are at the same potential. The hot is raised with respect to H & N. To everyone I know that is a transverse mode surge.
Seems to me in the past you said it was a common mode surge because N is raised with respect to absolute ground potential. Then everything is common mode. In my office all I can see is the hot rising and the neutral staying at ground wire potential. They taught me in school that was transverse mode. But maybe they had a hidden agenda.
There seems to be no science in common for a conversation.
--
bud--


Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

The problem is that "Ground" is not the same everywhere in a surge condition. I have seen 35v between 2 ground electrode systems less than 100' apart. That can spike quite a bit higher in a surge condition. If your cable or phone connection is not bonded to your local ground the service is using you can see significant transients between the cable and power. The other place you get in trouble is when you have a non-bonded connection between buildings (services) like a CAT5 LAN. At a big motel here we had 3 buildings that got connected together via LAN and we couldn't keep LAN cards in the PCs until we ran bonding conductors between them.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@aol.com wrote:

. I agree with all of that. I commonly write ground in quotes to try to emphasize they arent all the same. In previous posts I wrote about not only bonding signal entry protectors to the ground at the power service but the necessity of a *short* connection to limit the voltage developed between signal and power wires. Surge produced voltage between cable and power because of a long ground connection is the IEEE example I keep citing (staring pdf pg 40). Voltage between signal and power wires appears to be the major cause of damage to equipment. Martzloff has written "the impedance of the grounding system to `true earth' is far less important than the integrity of the bonding of the various parts of the grounding system." (But he probably has a hidden agenda.)
The comments questioned above were only whether a common mode surge coming in on power wires can get past the N-G bond in US services. And it is a side issue because plugin suppressors will protect from both common and transverse mode surges.
--
bud--

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Why do plug-in protectors never claim protection in numerical specs? Because a problem exists. It protects from transverse mode surges (the typically non-destructive type). But it has no earth ground. Therefore it cannot protect (divert, shunt, clamp, coneect) from common mode surges (the typically destructive surge). Need proof? Page 42 Figure 8.
Same important point is demonstrated by both front page articles in Electrical Engineering Times. To protect from the typically destructive surge requires single point earth ground, protectors with a short, dedicated connection to that single point ground, and a superior earthing 'system'.
Where is a common mode surge energy dissipated without damage? Not inside a protector. But a plug-in protector has no place else to dissipate surge energy. That energy must be connected short to earth ground so that energy is dissipated harmlessly in earth. How curious. That is exactly what a Bud citation says when it contradicts Bud:

Bud claims a plug-in protector is complete protection. If true, then the manufacturer would make that claim in numerical specs. Not one plug-in manufacturer dares to publish such numbers. Bud muist ignore hundreds of posts challenging him to provide those spec numbers. Bud cannot provide specs that don't exist.
Bud claims a plug-in protector will 'clamp to nothing' a common mode surge. Protector has all but no earthing connection - as both 'EE Times' front page articles demonstrate. Plug-in protector manufacturers cannot claim common mode protection. So manufacturer makes no claims for protection. Bud is spinning a lie that even the manufacturer will not make.
Essential to surge protection is ... well, time to quote but another industry profressional who demonstrates 'real world' protection: http://www.harvardrepeater.org/news/lightning.html

Another industry professional with decades of experience discusses the critical "low impedance" connection to earth. Bud's plug-in protectors have no such connection. Why do every responsible source require a 'low impedance' earthing connection - in direct contradiction to what Bud posts?
Bud 'clamps to nothing'. This industry professional says "you must present a low *impedance* path for the energy to go". Do we "clamp to nothing" or "clamp to earth"? Which one do we believe? The engineer with decades of proven experience? Or Bud whose citations even contradict Bud? Let's see. Even Francios Martzloff notes how plug-in protectors may contribute to damage of adjacent appliances - just like on Page 42 Figure 8.
A protector is only as effective as its earth ground. Bud now claims something new: that plug-in protectors without an earth connection will somehow, magically, provide common mode protection. Add that to his claim that protectors work by 'clamping to nothing'.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.