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Title: Generator and Amp protection?
Post by: Dave Mathew on November 18, 2011, 04:28:44 pm


    Hi, I am looking to do a bunch of outdoor shows next summer mainly electronic music with some live bands and have been researching generator and power needs. I also need to know what kind of protection I will need for these amps and powered speakers:

    2 Crown Itech4000's (on Bass duty)
    2 Mackie 1530 or 1521
    2 QSC k12's

    bbe crossover
    Mackie 1401
    Alesis compressor/limiter

    would a gen like this be enough power:
    http://www.homedepot.com/webapp/wcs/...cStoreNum=6155

    I would run the amps from the 30amp twistlock with 100 ft cable, and use the 20 amp circuits for everything else that has a smaller draw. I also have a 3000 watt honda gen for backup and or lights etc..

    I plan on getting some kind of power conditioner that has a voltimeter so I can keep watch on the voltage and would have a dummy load on too. I know that gfci's can pop easily, is there any other kind of protection that I would need for my gear?

Title: Re: Generator and Amp protection?
Post by: g'bye, Dick Rees on November 18, 2011, 04:41:14 pm

    Hi, I am looking to do a bunch of outdoor shows next summer mainly electronic music with some live bands and have been researching generator and power needs. I also need to know what kind of protection I will need for these amps and powered speakers:

    2 Crown Itech4000's (on Bass duty)
    2 Mackie 1530 or 1521
    2 QSC k12's

    bbe crossover
    Mackie 1401
    Alesis compressor/limiter

    would a gen like this be enough power:
    http://www.homedepot.com/webapp/wcs/...cStoreNum=6155

    I would run the amps from the 30amp twistlock with 100 ft cable, and use the 20 amp circuits for everything else that has a smaller draw. I also have a 3000 watt honda gen for backup and or lights etc..

    I plan on getting some kind of power conditioner that has a voltimeter so I can keep watch on the voltage and would have a dummy load on too. I know that gfci's can pop easily, is there any other kind of protection that I would need for my gear?

I think the link to HDepot is bogus.  I couldn't look at what you're looking at.
Title: Re: Generator and Amp protection?
Post by: Robert Weston on November 18, 2011, 04:56:57 pm
You should probably be looking at diesel generators.  They are substantially more quiet and (in my opinion) are more robust (stable current) than gas powered generators. 
Title: Re: Generator and Amp protection?
Post by: g'bye, Dick Rees on November 18, 2011, 05:01:35 pm
You should probably be looking at diesel generators.  They are substantially more quiet and (in my opinion) are more robust (stable current) than gas powered generators.

I doubt that the type of fuel has anything to do with the quality of the electricity produced......
Title: Re: Generator and Amp protection?
Post by: Dave Mathew on November 18, 2011, 05:23:04 pm
sorry try this link:
http://www.briggsandstratton.com/generators-pressure-washers/portable-generators/detail/?name=6000+Watt&id={1DA487B8-F445-43C3-B392-203A210FB292}

I cannot afford a diesel gen right now
Title: Re: Generator and Amp protection?
Post by: Mac Kerr on November 18, 2011, 05:32:43 pm
sorry try this link:
http://www.briggsandstratton.com/generators-pressure-washers/portable-generators/detail/?name=6000+Watt&id={1DA487B8-F445-43C3-B392-203A210FB292}

I cannot afford a diesel gen right now

Why buy when the production can rent?

Mac
Title: Re: Generator and Amp protection?
Post by: Dave Mathew on November 18, 2011, 05:39:24 pm
Why buy when the production can rent?

Mac

after a couple shows the generator will pay for itself, plus I have found that rentals are unreliable.

Title: Re: Generator and Amp protection?
Post by: g'bye, Dick Rees on November 18, 2011, 05:59:09 pm
sorry try this link:
http://www.briggsandstratton.com/generators-pressure-washers/portable-generators/detail/?name=6000+Watt&id={1DA487B8-F445-43C3-B392-203A210FB292}

I cannot afford a diesel gen right now

Depending on where you're working, generator size/type may or may not require a permit and inspection.  Where I am I can use up to a 5KW with no permit required.  Above that it costs for the permit and inspection.

It also matters how clean the power is.  The Hondas I have are inverter  AC and very clean and stable.  If you have the inverter series HOnda, just get another 3K and the Honda yoke kit to run them in phase together.  That'll give you the 6K you're looking for......and clean.
Title: Re: Generator and Amp protection?
Post by: Tim McCulloch on November 18, 2011, 08:12:37 pm
after a couple shows the generator will pay for itself, plus I have found that rentals are unreliable.
So you want to own a shitty generator that is unregulated?  What makes you think owning an unregulated (freq as well as voltage) generator is better than renting one?  See below... but in a nutshell, you've been renting the wrong generator, too.  And as Mac points out, why own when you can simply tell the promoter "a suitable generator is XYZ model from ABC rental shop."

The so-called "power conditioners" don't condition anything.  Any device that *does* make a material effect on the power at the current demand you will draw, will cost more than the HomeDespot generator.

When the HomeDespot genset pukes up it's windings, rings or carberator, do you want to be responsible to your client for the failure of their show?  Can you pay for the ticket refunds, damaged equipment (yours and a band or DJs)?

Trust us, the best deal in "own it yourself" generators is the Honda that Mr. Rees mentions.  For anything else you should rent a diesel generator like MQ, CAT, Spectrum, Agrekko or Kohler.  Seriously.

Tim Mc

Title: Re: Generator and Amp protection?
Post by: Dave Mathew on November 18, 2011, 09:27:09 pm
So you want to own a shitty generator that is unregulated?  What makes you think owning an unregulated (freq as well as voltage) generator is better than renting one?  See below... but in a nutshell, you've been renting the wrong generator, too.  And as Mac points out, why own when you can simply tell the promoter "a suitable generator is XYZ model from ABC rental shop."

The so-called "power conditioners" don't condition anything.  Any device that *does* make a material effect on the power at the current demand you will draw, will cost more than the HomeDespot generator.

When the HomeDespot genset pukes up it's windings, rings or carberator, do you want to be responsible to your client for the failure of their show?  Can you pay for the ticket refunds, damaged equipment (yours and a band or DJs)?

Trust us, the best deal in "own it yourself" generators is the Honda that Mr. Rees mentions.  For anything else you should rent a diesel generator like MQ, CAT, Spectrum, Agrekko or Kohler.  Seriously.

Tim Mc


I mentioned the power conditioner simply for the voltimeter. 
Ok I am convinced with Honda.  Could you explain to me about regulating freq?
thanks for your help
Title: Re: Generator and Amp protection?
Post by: g'bye, Dick Rees on November 18, 2011, 09:49:49 pm

I mentioned the power conditioner simply for the voltimeter.  And on the site that gen claims to have automatic voltage regulation.  Could you recomend a specific gen that would safely handle the equipment I have listed?  I know that it is not a huge system so Im looking for a solution within my budget.   Also could you explain to me about regulating freq too?
thanks for your help

Frequency:  60 cycles/second

What Honda model do you have now?  The most economical and practical thing to do is what I said before.  Get another matching Honda and the yoke kit to join them......if you have the inverter model.

Otherwise, forget trying to own.  I agree with rental.  With a consumer grade, unregulated generator it will be a dead heat between the number of times you use it to recoup your investment and the day that the crap power takes out your equipment........
Title: Re: Generator and Amp protection?
Post by: Dave Mathew on November 18, 2011, 10:18:19 pm
Frequency:  60 cycles/second

What Honda model do you have now?  The most economical and practical thing to do is what I said before.  Get another matching Honda and the yoke kit to join them......if you have the inverter model.

Otherwise, forget trying to own.  I agree with rental.  With a consumer grade, unregulated generator it will be a dead heat between the number of times you use it to recoup your investment and the day that the crap power takes out your equipment........

I have the Honda eb3000c it is not the inverter model. 
How about these:
http://www.hondapowerequipment.com/products/modeldetail.aspx?page=modeldetail&section=P2GG&modelname=EB5000&modelid=EB5000XK3

Could this provide steady enough voltage for the equipment that I listed?
I may be able to rent these locally
Title: Re: Generator and Amp protection?
Post by: g'bye, Dick Rees on November 18, 2011, 10:22:36 pm
I have the Honda eb3000c it is not the inverter model. 
How about these:
http://www.hondapowerequipment.com/products/modeldetail.aspx?page=modeldetail&section=P2GG&modelname=EB5000&modelid=EB5000XK3

Could this provide steady enough voltage for the equipment that I listed?
I may be able to rent these locally

The EB series is rated "industrial"......which means power tools, not sound gear.  Stop trying the "will this work" method.  Go with what you've been told WILL work.  That would be the Honda inverter models or renting a proper, regulated gen set.
Title: Re: Generator and Amp protection?
Post by: Dave Mathew on November 18, 2011, 10:32:30 pm
The EB series is rated "industrial"......which means power tools, not sound gear.  Stop trying the "will this work" method.  Go with what you've been told WILL work.  That would be the Honda inverter models or renting a proper, regulated gen set.

The reason I suggested it was because of this:
iAVR (Intelligent Automatic Voltage Regulator)

This generator offers an exclusive new Honda technology, iAVR (Intelligent Automatic Voltage Regulator). This consists of a digital capacitive discharge ignition, a self tuning regulator governor, a current transformer applied to the auto throttle and the new DAVR control unit.
iAVR lets the generator operate well above its maximum rating for up to 10 seconds to start high initial amp draw situations. This ensures a consistent flow of power regardless of the load, which translates into protection for sensitive equipment and reliable power for you.

Forgive me for not being knowledgeable however I am attempting to learn.

Maybe you could explain to me why the inverter is more apropriate and why?
Title: Re: Generator and Amp protection?
Post by: g'bye, Dick Rees on November 18, 2011, 10:50:10 pm
The reason I suggested it was because of this:
iAVR (Intelligent Automatic Voltage Regulator)

This generator offers an exclusive new Honda technology, iAVR (Intelligent Automatic Voltage Regulator). This consists of a digital capacitive discharge ignition, a self tuning regulator governor, a current transformer applied to the auto throttle and the new DAVR control unit.
iAVR lets the generator operate well above its maximum rating for up to 10 seconds to start high initial amp draw situations. This ensures a consistent flow of power regardless of the load, which translates into protection for sensitive equipment and reliable power for you.

Forgive me for not being knowledgeable however I am attempting to learn.

Maybe you could explain to me why the inverter is more apropriate and why?

Read all the product literature on the Honda website for each model you're considering.  Any model with an "i" in the designation has an inverter.......and is "computer safe" stable, clean power.  It's not just the regulated voltage, it's the wave form.  Honda is very clear about rating their units and state in each one what its capabilities are.  You need more than voltage regulation, intelligent or otherwise.

Buy whatever you want.  Your gear will last longer with inverter power.
Title: Re: Generator and Amp protection?
Post by: Dave Mathew on November 19, 2011, 02:37:22 am
Thanks now I understand a little more about inverter and the waves.  According to this page my gen(with cycloconverter) has a smoother wave than a brushless but not as smooth as one with an inverter.  http://www.hondapowerequipment.com/products/generators/content.aspx?asset=gg_choose

http://www.hondapowerequipment.com/products/generators/content.aspx?asset=gg_cycloconverter
Title: Re: Generator and Amp protection?
Post by: Jeff Bankston on November 19, 2011, 05:46:02 am
I doubt that the type of fuel has anything to do with the quality of the electricity produced......
you are right, fuel makes no difference, quality of gen does.
Title: Re: Generator and Amp protection?
Post by: Jeff Bankston on November 19, 2011, 05:50:48 am
after a couple shows the generator will pay for itself, plus I have found that rentals are unreliable.
i worked construction as a commercial electrician. b 4 the service was installed the gc rented a gen. usually a 45kva and day in day out on all the jobs i was on there was never a gen problem. very reliable and way cleaner the any power coming of the power line. a friend runs big jennys for the movie studios and worked as a touring sound engineer for some years. he love the clean power that a gen produces and i'm talking about an MQ or other quailty gen not an el cheepo. i wouldnt hook anything but a light bulb up to an elcheepo. something else , most cheep gens use an inverter like you buy for your car or truck to convert 12vdc to 120vac. this is awful power and not suitable for anything more then a light, microwave, or bullitproof milwaukee power tool.
Title: Re: Generator and Amp protection?
Post by: TJ (Tom) Cornish on November 19, 2011, 09:10:35 am
The Honda EU series generators are pretty much the only reasonable choice for a small generator for sound reinforcement, not only for the power quality issues already mentioned, but also because they are 10-20dB quieter in operation than the construction junk.
Title: Re: Generator and Amp protection?
Post by: Jeffrey Knorr - CobraSound.com on November 19, 2011, 09:38:12 am
Hi Dave,

Here is an example of the type of product that others in this thread are suggesting, http://www.multiquip.com/multiquip/ultra-silent.htm

The ideal is a super/ultra quiet diesel generator 25KVA or higher in rating.  You can usually rent such a unit for a few hundred dollars/weekend.  Having ample reliable power is the only way to run a successful show.  Also renting the unit rather than buying usually affords you greater protection in the case of an issue (i.e. quick service and/or backup units).

Any generators purchased from Home Depot will be far noisier, less reliable, and not produce as clean power.  The Generators that we're suggesting probably start at around $25k new and go up from there.

Jeff "Use the right tool for the job and sleep better at night"
Title: Re: Generator and Amp protection?
Post by: Ivan Beaver on November 19, 2011, 10:09:03 am
The Honda EU series generators are pretty much the only reasonable choice for a small generator for sound reinforcement, not only for the power quality issues already mentioned, but also because they are 10-20dB quieter in operation than the construction junk.
We have a 5Kw Honda that we use for moderate sized demos and field testing-where no power is available.

They are quiet-provide stable output and we have not had any issues with them.  And when pushed hard it appears as if they sag "gracefully".

Agreed-if you want ot do anythng "real", you HAVE to get a real regulated generator.  Otherwise you are just asking for trouble-which will cost much more in the end.
Title: Re: Generator and Amp protection?
Post by: Jon Geissinger on November 19, 2011, 12:20:33 pm
Use a diesel generator.  If you are worried about sags and peaks, then put an online UPS in the middle of the power chain or a power conditioner.  ALL of that stuff is very heavy!  But, the diesel generator is less prone to sags, a UPS will pick up any sags (long term sags) or a power conditioner will handle short sags.
I UPS will clean any other power issues as well (online UPS, actually runs off the batteries all the time instead of when there is a power outage).
Don't put lights on the same circuit as the sound equipment.
Just my 2 cents.
GENERALLY SPEAKING, Watts are watts, makes NICE conversion tools.
5KW amp and you plan on using it more than , 50% of the time at full power means 5KW input to the amp.
Northern (Tool and Equipment) has a 5.5KW (surge) genset for $1099, 407 lbs, electric start, 7 hours run time at half load.  Not a bad deal.
Watch for industrial sales of welder gensets.  Those can be quickly converted to what you need and they are already on a trailer.
Title: Re: Generator and Amp protection?
Post by: Ivan Beaver on November 19, 2011, 12:58:40 pm
  But, the diesel generator is less prone to sags, a UPS will pick up any sags (long term sags) or a power conditioner will handle short sags.
There are very few "conditioners" that will pick up "sags".  And for the size that you can run amps off of-they are going to be expensive.

Of course 5KW UPS's are not cheap-not light.

Almost all of the "conditioners" that are on the market are pretty much worthless.  A couple of MOV's hung across the line for spike protection. 

They do NOTHING for sags.  And when they blow-you have no way of knowing-so they are no longer providing any protection-even new it is a very limited protection.

For real protection- you need something like the Surge X products.  But (I could be wrong) I am not aware of the survgex providing any "pickup" for the sags.

I used a triplite unit for awhile on my FOH gear.  it was a switched transformer that would actually pick up the sags.  It worked well for awhile.  But then the switching started getting noisy-so I stopped using it.  It is good for the bench and constant loads-but musical surges don't cut it anymore.

Again the best thing is not to try and bandaid the situation and use the correct gen and you don't have to worry.
Title: Re: Generator and Amp protection?
Post by: Jonathan Johnson on November 19, 2011, 03:46:22 pm
GENERALLY SPEAKING, Watts are watts, makes NICE conversion tools.

Gensets are rated in volt-amps, not watts. Kilowatts are equal to kilovolt-amps ONLY for resistive loads; inductive loads can draw higher kVA than kW. The conversions for kW are what aren't so nice.

Still fairly simple, though-- multiply amps by volts and you get VA (A * V = VA). (A * V = W) only for resistive loads; for inductive loads, (A * V != W) due to power factor.

But you're safe to ignore all of that nitpicking and multiply the volts by the amps your devices draw to determine the kVA rating of the genset you need.
Title: Re: Generator and Amp protection?
Post by: Jeff Bankston on November 19, 2011, 04:11:39 pm
Gensets are rated in volt-amps, not watts. Kilowatts are equal to kilovolt-amps ONLY for resistive loads; inductive loads can draw higher kVA than kW. The conversions for kW are what aren't so nice.

Still fairly simple, though-- multiply amps by volts and you get VA (A * V = VA). (A * V = W) only for resistive loads; for inductive loads, (A * V != W) due to power factor.

But you're safe to ignore all of that nitpicking and multiply the volts by the amps your devices draw to determine the kVA rating of the genset you need.
+1 watch the terminolgy. the gens we rented were rated in KW. step down transformers like 480 to 120/208 are rated in KVA. my amps have both watt and amp draw on the back for the AC power. circut breakers and panels are rated in amps. it can get confusing. Home Depot sells a neat little pocket book called "UGLYS" with good electrical info and formulas in it. another thing you need to take in account is voltage drop if your running long power cords. VD is calculated by the length of wire run-gauge of wire-voltage-# of phases-amp draw. the uglys book has those formulas in it. 
Title: Re: Generator and Amp protection?
Post by: Ivan Beaver on November 19, 2011, 04:20:08 pm
Gensets are rated in volt-amps, not watts. Kilowatts are equal to kilovolt-amps ONLY for resistive loads; inductive loads can draw higher kVA than kW. The conversions for kW are what aren't so nice.

Still fairly simple, though-- multiply amps by volts and you get VA (A * V = VA). (A * V = W) only for resistive loads; for inductive loads, (A * V != W) due to power factor.

But you're safe to ignore all of that nitpicking and multiply the volts by the amps your devices draw to determine the kVA rating of the genset you need.
ANd then rent the next size up-just for overhead.  It is nice not to be running at max and you never know what else may need to be plugged into it-non audio or lighting related but still part of the event.
Title: Re: Generator and Amp protection?
Post by: Robert Weston on November 19, 2011, 06:22:33 pm
you are right, fuel makes no difference, quality of gen does.

Correct - my original comment referenced a higher reliability (and much, much quieter operation) with diesel generators rather than gas.
Title: Re: Generator and Amp protection?
Post by: g'bye, Dick Rees on November 19, 2011, 08:15:52 pm
Correct - my original comment referenced a higher reliability (and much, much quieter operation) with diesel generators rather than gas.

My Honda gasoline generators run as quiet or quieter than any of the diesel gen sets I've had to use, with the possible exception of a brand new Onan unit I once encountered.  Of course, they are smaller units, but size was not mentioned.  Only gas vs diesel.  As to reliability, I think that is a quality of construction and design issue unlinked to fuel type.

Both types require proper maintenance and I would agree that a diesel engine will have a longer useful life than a comparable gasoline engine.  But I cannot agree that gasoline generators are louder and less reliable.  There are other factors that come into play well before that.

It's just too much of a "blanket indictment" to hold up........
Title: Re: Generator and Amp protection?
Post by: Todd Rasmussen on November 21, 2011, 09:02:49 am
most cheep gens use an inverter like you buy for your car or truck to convert 12vdc to 120vac. this is awful power and not suitable for anything more then a light, microwave, or bullitproof milwaukee power tool.

I can't speak to the type of inverter used in most inverter gensets, but not all 12V inverters produce awful power. I have a 1kW Samlex pure sine wave inverter mounted in my work truck for some instrumentation stuff I use. The power is quite likely cleaner than what comes from the grid. Granted this is not power enough for a big show, but I have run some smaller audio gear from it and it worked perfectly.