devices for surge protection

MEXICOWANDERER wrote:
Jeysus an amateur. You are unaware of what an avalanche rectifier is yet you spout SAE hyperbole. I'm done...

28-32 volts as sufficient confirms facts are being invented rather than learned. Informed would learn numbers from either SAE or ISO (ie 270 volts on 12 volt electronics) before making a recommendations.

That 28-32 number demonstrates why other claims were so subjective. Posting a number exposed what was only speculation.

Same applies to effective RV protection. Progressive does what its numbers state. It is designed to avert common anomalies found in campgrounds. A reputation well deserved because it does well what it claims to do - and nothing more.

Jeysus an amateur. You are unaware of what an avalanche rectifier is yet you spout SAE hyperbole. I'm done...

pianotuna wrote:
You still have not answered my simple question, in a manner in which my pea sized brain can understand. Is the 20,000 amps type of event from a lighting strike?

Again:

A surge also known as a spike, transient, or direct lightning strike can even be a 20,000 amp microsecond event.

MEXICOWANDERER wrote:
Alternator avalanche rectifiers are rated 28-32 volts. Since they are in a major circuit they do limit total system transient voltage events to.......28 - 32 volts.
My personal ideal is SEVENTEEN POINT ZERO VOLTS clamping.

Automotive transients involve other factors and completely different solutions. This science is well defined by manufactures who design this stuff and by international standards.

SAE J1455 and ISO 7637-1 defined automotive transients up to 270 volts and energy up to 50 joules. These are high side or extreme numbers. Alternators rated at only 28-32 volts are woefully insufficient - easily fail.

SGS Thompson, one of many manufacturers who address this threat, define load dump (a destructive surge on 12 volt systems) as
peak voltage 80 to 100 volts and duration 300 to 400 milliseconds.

SGS Thompson also admits in a 1996 application notes that

The protection at the alternator level is a quite new concept and all the technical problems do not seem to be completely solved.

Electronics found in normal residential and commercial service are insufficient for automotive applications. Therefore automotive electronics tend to be more expensive. Power supply chips that operate up to 40 volt in most electronics are insufficient in automotive environments. Similar chips for automotive applications are rated at 60 or as much as 100 volts. Automotive environments are that harsh.

Automotive electronics are more expensive due to robust parts designed for and required for that harsh environment. Anything designed for 12 volt operation should withstand at least 60 volts.

Here is the intrinsic method of eliminating air conditioner motor unloading transients. This stops the process dead in it's tracks. Unfortunately incorporating this topology with soft start might as well be a ten pipe bong opium dream...

https://www.google.com/patents/US4506517

LOW VOLTAGE DIRECT CURRENT

Most automotive alternators and all EXPENSIVE automotive chassis 12-volt processors utilize transient voltage suppression in the form of avalanche rectifiers, and discrete component TVS circuitry. Field collapse of an automotive air conditioning magnetic CLUTCH, and starter motor and solenoid field collapse are NOT addressed. Neither is the effects of a GENERATOR starter motor armature and field winding collapse never mind the solenoid. Small 30-ampere rated Bosch type relays often contain a freewheel diode across the relay coil. This is like pis---- on a barn fire. Component failure of such items as TPS, CPS, MAS, are not examined due to possible compromising of potential replacement parts sales.

How many thousands of discrete DC components does a rig have? What is their rated design working voltage? Alternator avalanche rectifiers are rated 28-32 volts. Since they are in a major circuit they do limit total system transient voltage events to.......28 - 32 volts.

My personal ideal is SEVENTEEN POINT ZERO VOLTS clamping. Freewheeling fast response diodes across the AC clutch, starter motor, and solenoid and generator starter motor and solenoid.

But then again my vehicle electronics last virtually forever. Same with microwave, stereo, and monitors. Voltage correction is mandatory for AC circuits but TVS drainage is the magic bullet. For BOTH AC and vehicle battery system circuits.

westend wrote:

pianotuna wrote:
Hi Mex,

Yes, please. But with a wiring diagram for dummies in a parallel (not series) configuration (that would make it plug and play).

MEXICOWANDERER wrote:
If there is enough interest in this, I'll shop on eBay and post the seller links for the correct rated devices. REMEMBER minimum 4 devices except GDTs EACH buss. Four, L-N and four L-Ground 20 mm MOVs preferably 1500 watt TVSs. Six each would be better yet. Yes, fuses are vital for TVS circuit protection.

I've got both hands raised, yes, please.

Mex - please - with the title in block letters. For all us dummies here to see.

It wasn't aimed at you Don.

I fought ROTE ignorance for my entire career, flooded lead acid batteries and DC alternator design. Folks who read books and then parrot whatever they read are like my Dr. who insisted I receive blood thinners BY ROTE and damned near turned me hemophiliac. Utter, blatant, and somewhat arrogant rote reaction.

I have time to build an eight dollar circuit to protect $500 worth of IC controlled appliances. What I do not have is the $500 to replace them because ROTE blathering says I do not need transient voltage protection. I can ID a rote spewer within a couple of minutes because they love to camouflage lack of experience with a blanket of spurious claims not specifically directed at a concise subject target. Talk about transient events, they blather long term "surges" of over-voltage. Talk about enhancement of lightning ionization pathways (at the power pole) and the next thing you know they'll have your gas discharge tube device inside your coffeemaker.

The idea is to gain a product that commercial enterprises find to be horribly confused with a POS power strip. Constructing a PROPER transient diversion device (It cannot "absorb" events - it diverts them) can be obtained in $200 - $300 DOLLAR specialty devices. If these devices were fraudulent the companies (Try Tripp-Lite) would have long ago gone out of business. And like it or not, MOVs degrade. All devices DEMAND individual component safety fusing. Something easily done on a hobby bench but horribly expensive to design, UL ETL or CSA certify, market and distribute. Pay $300 for eight dollars worth of discrete components? Makes perfect sense to spewers of shotgun grade ROTE. I've zero time to deal with misdirected nonsense.

Add MOVS. Use eight devices per route (Line to neutral line to earth ground). Multiply TVS total devices. Share the load. Lengthen suppressor lifespan.

Don, your math is impeccable and irrefutable for your situation. Good job.

I hobble
I hobble
And with one hand
Home-made circuits I shall cobble

Hi Mex,

Perhaps because I'm a piano tuner? I research as well as I can. I try to give honest answers. I protect what I can within my (limited) budget. I buy the best quality I can within that budget. When I find something that works, I share it with others.

In an ideal world, my RV would have 1600 watts of solar and 1000 amp-hours of battery bank. In a possible world that would have to be only 556 amp-hours of storage. In a world with a budget, I spent 1700 bucks in 2005 to get 256 watts of solar which works exactly as planned and continues to do so.

What is changed is that I became a full time RV'er. Today that 1700 would buy me 850 watts of solar materials--but to be able to install that I'd have to add an aluminum rack covering the entire roof. That, including 1600 watts of solar would cost about 6 grand. At $1.25 per liter (for premium fuel) I can get 4800 liters which would fill the generator 370 times. At 1/4 load that is 6000 hours of run time. The economics (for me) just don't work.

Since my full time days may end in 4 years, pay back is not really possible.

I'm in serious danger of becoming a "power pole princess".

T.S. Elliot describes me well.

"I grow old … I grow old …
I shall wear the bottoms of my trousers rolled."

8/20ths of 1 60Hz cycle Don. Incredibly tiny time frame.

Apparently the forum has gained another master of rote.

Individual service drop DELTA (we have WYE down here) transformers have H1 - H2 fusible links. A campground not only has a common circuit - the huge fusible link high voltage feeds offer no protection.

BEST protection comes from MULTIPLE protective devices. Incorrect connection, a device to protect load from long duration events PLUS a device to protect against out-of-range discrete component protection TRANSIENT VOLTAGE EVENTS. Ever hear of "punching holes in P/N junctions"? It is caused by cumulative joule violations of the rating of the device.

PG&E, SCE, LAPWD, Sierra Pacific Power will pay for damages incurred from a "Their Fault" equipment failure. There is no protection from a 12.5 Kv accident except for fusible links on service drop transformers.

GAS DISCHARGE TUBE devices buy time. Most are rated 220 V peak to peak

Why do I feel I am answering an "informed" amateur's questions?

Westom,

You still have not answered my simple question, in a manner in which my pea sized brain can understand. Is the 20,000 amps type of event from a lighting strike?