Posted by garylav on November 29, 2006, 11:30 am
We have a DR2424 Trace Inverter with charger that has been on line
since November of 2000. In July of this year we experienced a severe
lightning storm like none we had ever had in our area (southern
Vermont). We turned off the inverter but heard a loud snapping noise
inside the house (the inverter is located in the barn about fifty feet
away from the house). After the storm passed we turned the inverter
back on. It was operating properly except our generator backup was not
turning the automatic charger on. We sent it to Tekris, the nearest
Trace repair facility, in New Jersey. They replaced two diodes to
correct a faulty AC input. We purchased (from New England Solar
Electric) a brand new Xantrex DR2424 to replace the damaged unit while
it was being repaired so that we would have backup for any future
problems.
In August of this year we experienced another severe electrical storm
and turned off the inverter. During the storm the same snapping noise
occurred in the house. After turning the inverter back on, we had a
blinking red light , which indicated a serious fault with the unit. We
shipped that one to Tekris and installed our original inverter. Tekris
told us that the second inverter (the brand-new one) apparently had
experienced a blown motherboard due to lightning, and recommended we
disconnect all circuit breakers, DC disconnect, and array disconnect in
addtion to turning off the inverter.
Recently we experienced a third electrical storm with the same snapping
noise. Same problem as the first time: no AC input. We sent the
inverter to Tekris but did not tell them about the lightning, and they
told us it was probably over-voltage from the generator. They replaced
two diodes of the AC input, the exact same repair as the first time.
Nowhere on any of the lightning arresters or equipment were there any
signs, such as burned wires or blackening.
Our generator has always worked the charging unit with no problems,
which leads me to believe that the voltage regulator is operating
properly and that all of our problems have to do with some type of
electrical surge from the lightning storms. Precautions we have in
place are (1) bonded grounding system--three ground rods and 200 feet
of unshielded copper grounding wire; (2) lightning arresters in place
on DC disconnect, deep-well pump, circuitbreaker box for AC feed from
the inverter, and circuitbreaker box from generator to inverter (AC
input). We have been told by two different sources that this is the
best we can do. Also, our solar equipment supplier told us he has had
more complaints about severe electrical storms in the past six months
than in the twenty years he has been dealing with solar power. (We
have, since 2000, experienced other lightning storms. We always turned
the inverter off and never had a problem.)
My question is: how do we prevent this from happening! Any suggestions
would be much appreciated.
Thank you!
Posted by SJC on November 29, 2006, 2:40 pm
This may sound counter intuitive, but maybe you do not want to turn it off.
The inverter may be able to track with what is going on with the line if it is
on, but not when it is off. I sounds like you have surge and lightening
suppressors
in the right places throughout your installation, so it does not sound like
adding more
would help. I would make sure I have a fast varistor type right on the inverter
where
it connects to the line AC. Just a guess, since I have no real experience with
these inverters.
> We have a DR2424 Trace Inverter with charger that has been on line
> since November of 2000. In July of this year we experienced a severe
> lightning storm like none we had ever had in our area (southern
> Vermont). We turned off the inverter but heard a loud snapping noise
> inside the house (the inverter is located in the barn about fifty feet
> away from the house). After the storm passed we turned the inverter
> back on. It was operating properly except our generator backup was not
> turning the automatic charger on. We sent it to Tekris, the nearest
> Trace repair facility, in New Jersey. They replaced two diodes to
> correct a faulty AC input. We purchased (from New England Solar
> Electric) a brand new Xantrex DR2424 to replace the damaged unit while
> it was being repaired so that we would have backup for any future
> problems.
>
> In August of this year we experienced another severe electrical storm
> and turned off the inverter. During the storm the same snapping noise
> occurred in the house. After turning the inverter back on, we had a
> blinking red light , which indicated a serious fault with the unit. We
> shipped that one to Tekris and installed our original inverter. Tekris
> told us that the second inverter (the brand-new one) apparently had
> experienced a blown motherboard due to lightning, and recommended we
> disconnect all circuit breakers, DC disconnect, and array disconnect in
> addtion to turning off the inverter.
>
> Recently we experienced a third electrical storm with the same snapping
> noise. Same problem as the first time: no AC input. We sent the
> inverter to Tekris but did not tell them about the lightning, and they
> told us it was probably over-voltage from the generator. They replaced
> two diodes of the AC input, the exact same repair as the first time.
> Nowhere on any of the lightning arresters or equipment were there any
> signs, such as burned wires or blackening.
>
> Our generator has always worked the charging unit with no problems,
> which leads me to believe that the voltage regulator is operating
> properly and that all of our problems have to do with some type of
> electrical surge from the lightning storms. Precautions we have in
> place are (1) bonded grounding system--three ground rods and 200 feet
> of unshielded copper grounding wire; (2) lightning arresters in place
> on DC disconnect, deep-well pump, circuitbreaker box for AC feed from
> the inverter, and circuitbreaker box from generator to inverter (AC
> input). We have been told by two different sources that this is the
> best we can do. Also, our solar equipment supplier told us he has had
> more complaints about severe electrical storms in the past six months
> than in the twenty years he has been dealing with solar power. (We
> have, since 2000, experienced other lightning storms. We always turned
> the inverter off and never had a problem.)
>
> My question is: how do we prevent this from happening! Any suggestions
> would be much appreciated.
>
> Thank you!
Posted by Gerry on November 29, 2006, 6:12 pm
garylav wrote:
> We have a DR2424 Trace Inverter with charger that has been on line
> since November of 2000. In July of this year we experienced a severe
> lightning storm like none we had ever had in our area (southern
> Vermont). We turned off the inverter but heard a loud snapping noise
> inside the house
high voltage arc over or hot wires in contact (co-incidence?)
> (the inverter is located in the barn about fifty feet
> away from the house).
50 feet of wires make a good antenna to receive a lightning pulse
> After the storm passed we turned the inverter
> back on. It was operating properly except our generator backup was not
> turning the automatic charger on. We sent it to Tekris, the nearest
> Trace repair facility, in New Jersey. They replaced two diodes to
> correct a faulty AC input.
diodes failed from over volage
> We purchased (from New England Solar
> Electric) a brand new Xantrex DR2424 to replace the damaged unit while
> it was being repaired so that we would have backup for any future
> problems.
> In August of this year we experienced another severe electrical storm
> and turned off the inverter. During the storm the same snapping noise
> occurred in the house. After turning the inverter back on, we had a
> blinking red light , which indicated a serious fault with the unit. We
> shipped that one to Tekris and installed our original inverter. Tekris
> told us that the second inverter (the brand-new one) apparently had
> experienced a blown motherboard due to lightning, and recommended we
> disconnect all circuit breakers, DC disconnect, and array disconnect in
> addtion to turning off the inverter.
> Recently we experienced a third electrical storm with the same snapping
> noise. Same problem as the first time: no AC input. We sent the
> inverter to Tekris but did not tell them about the lightning, and they
> told us it was probably over-voltage from the generator.
or from the lightning?
> They replaced
> two diodes of the AC input, the exact same repair as the first time.
its consistent...haha..
> Nowhere on any of the lightning arresters or equipment were there any
> signs, such as burned wires or blackening.
> Our generator has always worked the charging unit with no problems,
> which leads me to believe that the voltage regulator is operating
> properly and that all of our problems have to do with some type of
> electrical surge from the lightning storms. Precautions we have in
> place are (1) bonded grounding system--three ground rods and 200 feet
> of unshielded copper grounding wire;
200 foot antenna GREAT for capturing giant electro-magnetic pulse...
I used to hook my antenna up to a 8ft neon lamp other end to ground/water
pipe and lamp would even start flickering before the lighting
discharge...which of course really light up the neon.......free
electricity..hahaa....but I would NOT recommend using diodes to try make DC
out of such a pulse!!!
Get rid of the 200 foot ground wire..make one minimum 6ft or less to a real
good copper into sand/clay with rock salt in it....or float the
inverter/batteries of where-ever they are grounded...
Go figure out all your possible ground loops in your system...including the
house wiring...even a wall switch or socket arc overs.......you will find
it
> (2) lightning arresters in place
> on DC disconnect, deep-well pump, circuitbreaker box for AC feed from
> the inverter, and circuitbreaker box from generator to inverter (AC
> input). We have been told by two different sources that this is the
> best we can do. Also, our solar equipment supplier told us he has had
> more complaints about severe electrical storms in the past six months
> than in the twenty years he has been dealing with solar power. (We
> have, since 2000, experienced other lightning storms. We always turned
> the inverter off and never had a problem.)
> My question is: how do we prevent this from happening! Any suggestions
> would be much appreciated.
> Thank you!
Ground loops are a scary thing that can be fixed...
Seems too important not to get this fixed..
hope I helped!!
Gerry
Posted by w_tom on November 29, 2006, 7:11 pm
Appreciate that well over 90% of all trees struck by lightning leave
no indication. Just because you find no strike indication tells us
little. Assuming the diodes are a victim of a lightning strike, then
lightning has formed a connection from cloud to earth (maybe miles
distant) via those diode. You task is to determine any path to earth
via those diodes and then earth that path. Earthing is what a surge
protector is for. Some AC wires cannot be earthed directly. So we use
a protector to make a 'less than 10 foot' connection to that earthing
electrode. Any wire to those diodes that is first earthed, then, would
not conduct lightning to earth via the diodes.
An industry professional demonstrates the concept. In this figure
are two structures. Each structure can be a building, antenna, or
solar array panel. Makes little difference since any structure can
connect a direct lightning strike into diodes inside other structure.
Each structure has its own single point ground. Notice each ground
is a loop. Another solution is one or a network of ground rods. Point
is that every wire entering or leaving the structure first connects to
that structure's single point earth ground. All wires must connect,
short, to the same earthing electrode. Earthing connection is made
either by hardwire or via a surge protector. Does not matter whether
incoming wire is overhead or underground. See the figure:
http://www.erico.com/public/library/fep/technotes/tncr002.pdf
To make both earthing systems even more effective, a buried
connection is made between those two earthing electrodes.
When two structures are wired together, then the second structure is
nothing more than a 'lightning rod' connected to electronics in the
first structure. To electrically separate that 'lightning rod' from
the other building - single point earthing connects to every wire in
every cable. This may explain why those same diodes are damaged by
lightning.
So other points. Turning something off solves nothing. Early 1900
Ham radio operators would disconnect the antenna, put that lead inside
a mason jar, and still suffer damage. Damage stopped when the antenna
lead was earthed. Do you think that power switch will stop what three
miles of sky could not?
Protectors without earthing accomplish nothing. In fact, protectors
adjacent to electronics can even contribute to damage of those
electronics. Protector are best located far from electronics and as
close to the single point earthng as possible.
garylav wrote:
> We have a DR2424 Trace Inverter with charger that has been on line
> since November of 2000. In July of this year we experienced a severe
> lightning storm like none we had ever had in our area (southern
> Vermont). We turned off the inverter but heard a loud snapping noise
> inside the house (the inverter is located in the barn about fifty feet
> away from the house). After the storm passed we turned the inverter
> back on. It was operating properly except our generator backup was not
> turning the automatic charger on. We sent it to Tekris, the nearest
> Trace repair facility, in New Jersey. They replaced two diodes to
> correct a faulty AC input. We purchased (from New England Solar
> Electric) a brand new Xantrex DR2424 to replace the damaged unit while
> it was being repaired so that we would have backup for any future
> problems.
> In August of this year we experienced another severe electrical storm
> and turned off the inverter. During the storm the same snapping noise
> occurred in the house. After turning the inverter back on, we had a
> blinking red light , which indicated a serious fault with the unit. We
> shipped that one to Tekris and installed our original inverter. Tekris
> told us that the second inverter (the brand-new one) apparently had
> experienced a blown motherboard due to lightning, and recommended we
> disconnect all circuit breakers, DC disconnect, and array disconnect in
> addtion to turning off the inverter.
> Recently we experienced a third electrical storm with the same snapping
> noise. Same problem as the first time: no AC input. We sent the
> inverter to Tekris but did not tell them about the lightning, and they
> told us it was probably over-voltage from the generator. They replaced
> two diodes of the AC input, the exact same repair as the first time.
> Nowhere on any of the lightning arresters or equipment were there any
> signs, such as burned wires or blackening.
> Our generator has always worked the charging unit with no problems,
> which leads me to believe that the voltage regulator is operating
> properly and that all of our problems have to do with some type of
> electrical surge from the lightning storms. Precautions we have in
> place are (1) bonded grounding system--three ground rods and 200 feet
> of unshielded copper grounding wire; (2) lightning arresters in place
> on DC disconnect, deep-well pump, circuitbreaker box for AC feed from
> the inverter, and circuitbreaker box from generator to inverter (AC
> input). We have been told by two different sources that this is the
> best we can do. Also, our solar equipment supplier told us he has had
> more complaints about severe electrical storms in the past six months
> than in the twenty years he has been dealing with solar power. (We
> have, since 2000, experienced other lightning storms. We always turned
> the inverter off and never had a problem.)
> My question is: how do we prevent this from happening! Any suggestions
> would be much appreciated.
Posted by nicksanspam on November 29, 2006, 10:56 pm
> Protectors without earthing accomplish nothing...
Nonsense. Chokes can work fine.
Nick
XML site map
> since November of 2000. In July of this year we experienced a severe
> lightning storm like none we had ever had in our area (southern
> Vermont). We turned off the inverter but heard a loud snapping noise
> inside the house (the inverter is located in the barn about fifty feet
> away from the house). After the storm passed we turned the inverter
> back on. It was operating properly except our generator backup was not
> turning the automatic charger on. We sent it to Tekris, the nearest
> Trace repair facility, in New Jersey. They replaced two diodes to
> correct a faulty AC input. We purchased (from New England Solar
> Electric) a brand new Xantrex DR2424 to replace the damaged unit while
> it was being repaired so that we would have backup for any future
> problems.
>
> In August of this year we experienced another severe electrical storm
> and turned off the inverter. During the storm the same snapping noise
> occurred in the house. After turning the inverter back on, we had a
> blinking red light , which indicated a serious fault with the unit. We
> shipped that one to Tekris and installed our original inverter. Tekris
> told us that the second inverter (the brand-new one) apparently had
> experienced a blown motherboard due to lightning, and recommended we
> disconnect all circuit breakers, DC disconnect, and array disconnect in
> addtion to turning off the inverter.
>
> Recently we experienced a third electrical storm with the same snapping
> noise. Same problem as the first time: no AC input. We sent the
> inverter to Tekris but did not tell them about the lightning, and they
> told us it was probably over-voltage from the generator. They replaced
> two diodes of the AC input, the exact same repair as the first time.
> Nowhere on any of the lightning arresters or equipment were there any
> signs, such as burned wires or blackening.
>
> Our generator has always worked the charging unit with no problems,
> which leads me to believe that the voltage regulator is operating
> properly and that all of our problems have to do with some type of
> electrical surge from the lightning storms. Precautions we have in
> place are (1) bonded grounding system--three ground rods and 200 feet
> of unshielded copper grounding wire; (2) lightning arresters in place
> on DC disconnect, deep-well pump, circuitbreaker box for AC feed from
> the inverter, and circuitbreaker box from generator to inverter (AC
> input). We have been told by two different sources that this is the
> best we can do. Also, our solar equipment supplier told us he has had
> more complaints about severe electrical storms in the past six months
> than in the twenty years he has been dealing with solar power. (We
> have, since 2000, experienced other lightning storms. We always turned
> the inverter off and never had a problem.)
>
> My question is: how do we prevent this from happening! Any suggestions
> would be much appreciated.
>
> Thank you!