Cart battery power

[Bartek]

Hi there,

I'm looking to upgrade my old 33ah batts. As my cart grew over the years, it has become a power guzzling monster and my 33's feel to fatigued. I've had the MK battery brand batts for years. Just wondering what ya'll using, any new revolutionary products out there?? let me know.

Bartek

[Glen Trew]

I'm looking to upgrade my old 33ah batts...

Bartek

Something to consider is the Remote Audio MEON AC/DC/Battery supply. (now shipping) Check it out here: http://www.trewaudio.com/meon.htm.

How many amps does your cart draw?

Glen Trew

[Sergio Sanmiguel]

Something to consider is the Remote Audio MEON AC/DC/Battery supply. (now shipping) Check it out here: http://www.trewaudio.com/meon.htm.

How many amps does your cart draw?

Glen Trew

Hello Glen,

Do you think it would make sense to add a AC output jack on the MEON, for lets say plug a laptop computer?

[Glen Trew]

Hello Glen,

Do you think it would make sense to add a AC output jack on the MEON, for lets say plug a laptop computer?

Good point, but I don't think so (assuming you mean an internal DC-AC inverter). it would add weight, expense, size, and possible noise issues for many who would not need the inverter. Also, some might need a large inverter while others only a small inverter. For those who need and inverter, I think the best answer is to buy the size/type needed and power it with one of the MEON's 12 outlets.

Part of the beauty of the MEON is that's self-contained (battery, charger, AC-DC supply, distribution, and meters) in a single 2-rackspace chassis weighing just 25 pounds.

Glen Trew

Glen Trew

[Sergio Sanmiguel]

Good point, but I don't think so (assuming you mean an internal DC-AC inverter). it would add weight, expense, size, and possible noise issues for many who would not need the inverter...

I see what you mean. Also there's a DC to Magsafe adaptor you can probably hook up to a 12v dc output for those using with a MacBook.. But still would be nice to have a regulated AC on the back of the MEON for when connected to AC

...Maybe only for utility proposes (?)

[Glen Trew]

I see what you mean... But still would be nice to have a regulated AC on the back of the MEON for when connected to AC...

quote]

There is room on the chassis for a loop-through AC connector (like the type you see on the back of computer power supplies), but not a full size Edison type connector. What may look like unused space on the back of the MEON is actually used to heat-sync the AC-DC supply.

Glen Trew

[Philip Perkins]

There is no better battery than the marine series (blue top) Optima D31M. Best warranty. Best packaging.

Does that battery really weigh 60 pounds?

Philip Perkins

[Sergio Sanmiguel]

Hey Scott,

What charger are you using for the Optima D31M?

How long it takes to charge & how often you need to recharge it?

[Sergio Sanmiguel]

Sweet!

BTW your next post will be # 1000!!!

Never mind...

[Steve Joachim]

The PSC Powermax has been replaced by the Powermax Ultra. The Powermax Ultra differs from the Meon in several areas. First, it offers 30 amps of power.  The Meon max's out at 18. It will output three different voltages (12V, 6V, 15V). The Meon ouputs 12V only. The Powermax Ultra also uses dual redundant power supplies and offers output filtering to protect against intermod noise. The internal battery feature of the Meon could be very usefull for many customers. However, the 3.9 amp battery charger on the Meon is going to give you a pretty long charge cycle v.s the PSC which will charge at up to 30 amps. They are both good products. It just depends on how much power you are going to draw and exactly what your powering needs might be.

[Glen Trew]

...The Powermax Ultra differs from the Meon in several areas. First, it offers 30 amps of power.  The Meon max's out at 18. It will output three different voltages (12V, 6V, 15V). The Meon ouputs 12V only. The Powermax Ultra also uses dual redundant power supplies and offers output filtering to protect against intermod noise. The internal battery feature of the Meon could be very usefull for many customers. However, the 3.9 amp battery charger on the Meon is going to give you a pretty long charge cycle v.s the PSC which will charge at up to 30 amps. They are both good products. It just depends on how much power you are going to draw and exactly what your powering needs might be.

Like Steve J. said, the Powermax and Meon, though somewhat similar, offer some different features for different priorities, and Trew Audio has sold both types to happy customers. In a nutshell, if someone needs 66A/hr of capacity on a daily basis, then the Powermax is for them. But if that much capacity is not always needed, then dealing with the fans, extra bulk, weight and performance limitations of external lead acid batteries is not necessary. For the daily on-set situations that I encounter with a sound cart on movies and commercials, many will prefer the Meon.

Knowing which is best for you is not nearly as simple as one having more capacity than the other, so, just to make sure all the comparisons are out there and understood:

The Powermax can deliver up to 30A continuous to a cart, but this assumes the batteries are either fully charged or disconnected and that the fans are running. Likewise, the charge time of 2.5 hours per battery becomes 5 hours with both batteries, and assumes that the nothing on the cart is being powered. As power is used for the cart, the recharge time increases.

The Meon’s AC-DC supply is never used for charging the battery, so the Meon will deliver its full capacity of 18A to the cart, even while a fully drained battery is being charged, with no fans running. The full capacity of the charger is always available for the battery, which charges in 6 hours or less.

So, in actuality, the difference in capacity and charge time between the Meon and Powermax is not what the numbers suggest at first glance. In fact, when a battery is being charged, the Powermax can have less power available for the cart than the Meon. Likewise, when providing 18A to a cart, the Meon will recharge faster than the Powermax.

The Meon is 2 rack spaces. The Powermax is 2 rack spaces. The Meon is self-contained, including the battery. The Powermax requires a user-supplied external lead acid battery or two, of 33 amps minimum each (a smaller lead acid battery would be damaged by the internal charger). The SLA batteries must be put somewhere else on the cart, attached with Speakon connectors..

The vast majority of sound carts pull less than 10 amps, so the Meon’s internal 29A/hr NiMH battery (up from last year’s 27A/hr version) will keep most carts going for at least three hours. Since AC power is usually available except for occasional interruptions, additional battery capacity may never be needed. However, if a longer period without AC is expected, external lead acid batteries of any size can be plugged into the Meon’s 13A outlets. The Meon will float-charge and properly maintain an external lead acid battery at 13.8VDC when AC is available.

The Powermax is limited to 4A for each 12V outlet, which (for example) cannot power DC-AC inverters of the size needed to power the Yamaha 01V mixer that requires more than 6A at 12V. It also means that multiple cables must be used from the Powermax to supply power to even low current consumption sound carts.

Of the 12 outlets on the Meon, 4 have a capacity of 13 amps, allowing a single output cable to power most sound carts if desired, and to power DC-AC inverters for large devices (like the Yamaha O1V). The remaining 8 outlets are capable of 6 amps each.

The Meon is completely quiet because it does not use any fans. The Powermax uses fans for cooling.

The Powermax relies on lead acid batteries that weigh, amp per amp, much more than the Meon’s Nickel Metal Hydride battery. NMH batteries also deliver high current more efficiently than SLA batteries, meaning that a 29A/hr NMH battery will last longer in high current draws (10 amps or more) than a typical 33A/hr SLA battery.

The Meon weighs a total of 25 pounds, including the internal 29A/hr NMHi battery. The Powermax in a similar configuration (with 33A/hr battery attached) weighs 42 pounds (12 pounds plus another 30 pounds for a typical 33A/hr SLA Pelican style battery).

The Meon has a volt meter, an amp meter, a fuel gauge, and a charge progress indicator. The Amp meter is particularly useful in knowing exactly how much current each device in your cart requires and how much your entire cart is drawing at any given moment.

I hope these additional details make the difference/similarities and pros/cons more clear. More info is available at these two sites: http://www.professionalsound.com/Catalog/Powermax%20Ultra.htm and

http://remoteaudio.com/meon.htm

Glen Trew

[t.elder]

However, if a longer period without AC is expected, external lead acid batteries of any size can be plugged into the Meon’s 13A outlets. The Meon will float-charge and properly maintain an external lead acid battery at 13.8VDC when AC is available.

Glen Trew

I looked over your literature on the Meon, but didn't realize that it had this capability - very impressive.

Tim

[Bartek]

Hey Scott what kind of case do you use to house the Optima D31M?

[mikefilosa]

I use a rubber strap to hold it against the cart. I choose to show off the battery since I think it looks cool.

And it does! --- saw some of the Optima Line at the local CostCo just last night ...

Mike Filosa, CAS

Atlanta

[FSBELLA]

I looked over your literature on the Meon, but didn't realize that it had this capability - very impressive.

Tim

Hey guys,

The one feature I like, is the built in batts. no need for the 12v pelican batts anymore.

[Steve Joachim]

Thanks to Glen for the detailed comparison between the Meon and the PSC Powermax Ultra. I learned more about the product than I knew from looking at the spec sheet. My only quibble would be that our recent experience here is that many of today's sound carts actually do pull more than 10 amps. The original Powermax was discontinued largely because even 14 amps was becoming not enough for many of our customers. Thus the need for the Ultra version.

[Ron Meyer]

Glen Trew is a great guy and an asset to this industry.  I look forward to seeing him at the upcoming NAB show and will be the first to buy him a beer.  I am not trying to undermine him in any way.  I would just like to correct some of the misunderstandings he has about our PSC PowerMax Ultra. 

The PSC PowerMax Ultra has been on the market for a year now and has proven itself many times over.  We have more than 150 of these operating worldwide.  The following are corrections to some of the statements made about our product.

Glen’s comments are shown in "quotations" and my replies are in bold.

Thank you for your time.

Sincerely

Ron Meyer

Professional Sound Corp.

“Knowing which is best for you is not nearly as simple as one having more capacity than the other, so, just to make sure all the comparisons are out there and understood:” Glen Trew

I could not agree more with this statement.  Capacity is just one of the specifications a user should consider.  But if you really want to have all of the comparisons understood, then consider the following:

1. The PSC PowerMax Ultra is equipped with output filters on each of the 36 separate power output pins.  Yes there are 36 because the PSC PowerMax Ultra offers 3 different output voltages on each of its 12 output connectors.  Someone will try and tell you that these output filters are not needed, but I will disagree. I would not spend the money, printed circuit board space and time to install these filters if I did not think they were absolutely necessary.  Nearly all audio equipment built today use internal DC to DC converters.  These all generate some electrical switching noise and this noise finds it’s way out the power lines.  When two pieces of equipment are operated from the same power source, the two DC to DC converters can and will beat against each other and create audible noise.  The filters help eliminate this intermodulation of DC to DC switching noise.  Here at PSC we have been including output filters for more than 10 years.

2. Each of these 36 possible outputs has it’s own polyfuse for protection and each of these 36 fuses are monitored via bi-color LED’s on the front panel.  If any piece of your audio package has an over current problem, you will know it right away.  We are the only company that offers this feature.

3. Our PowerMax Ultra outputs three different voltages to operate a vast majority of the equipment being used today.  6Vdc (internally adjustable from 5Vdc to 9Vdc),  12Vdc and 15Vdc (internally adjustable from 15 to 24Vdc).  We are the only company that offers this feature.

4. The PSC PowerMax Ultra is RoHS compliant and CE approved for sale and use in Europe and other countries.  In addition, it will operate from 100 to 240Vac for worldwide use without adjustment.  The Meon specifications published on their website make no mention of AC voltage range, RoHS compliance or CE compliance.  These are important issues if you plan on selling, shipping or using your gear outside of the USA.    Universal input voltage is a must in today’s world……and especially on film sets where power is troublesome at best. 

“The Powermax can deliver up to 30A continuous to a cart, but this assumes the batteries are either fully charged or disconnected and that the fans are running. Likewise, the charge time of 2.5 hours per battery becomes 5 hours with both batteries, and assumes that the nothing on the cart is being powered. As power is used for the cart, the recharge time increases.” Glen Trew

This is inaccurate.  The PSC Powermax Ultra is equiped with two battery charger circuits so if you are using a second battery, the charge time does not increase.  The 2.5 Hour charge time is based on a 33 Amp battery and is a conservative figure.  If you are using only one 33 amp battery, then the other 15 amp supply is available fully to operate the cart.  I don’t think there is any point in comparing charge times of two 33 amp hour batteries when the Meon is only equipped with one 29 amp hour battery.

“The Meon’s AC-DC supply is never used for charging the battery, so the Meon will deliver its full capacity of 18A to the cart, even while a fully drained battery is being charged, with no fans running. The full capacity of the charger is always available for the battery, which charges in 6 hours or less.”  Glen Trew

The PSC PowerMax Ultra’s power supplies are shared and redundant for the sake of reliability in the field. The PSC PowerMax Ultra has 30 amps available at all times.  These 30 amps can be used for charging and/or cart operation.  Its fully automatic and not something the user even needs to think about.   

“So, in actuality, the difference in capacity and charge time between the Meon and Powermax is not what the numbers suggest at first glance. In fact, when a battery is being charged, the Powermax can have less power available for the cart than the Meon. Likewise, when providing 18A to a cart, the Meon will recharge faster than the Powermax.”  Glen Trew

This is inaccurate.  An 18 amp power supply and a 5 amp charger simply cannot offer more power output that two 15 amp power supplies that offer a combined output of 30 amps.  The fact is, when providing 18 amps to the cart, the PSC PowerMax still has 12 amps left over for charging.  12 amps are more than 5 amps any way you look at it.

“The Meon is completely quiet because it does not use any fans. The Powermax uses fans for cooling.” Glen Trew

Yes it does, and they were carefully designed to be very slow turning, low noise fans.  In addition, they can be shut down during film takes via your remote roll system or a simple switch.  Our customers report that in most cases, the fans are a non–issue because the sound cart is often located away from the set these days due to the noise generated by DVD burners, etc.

“I hope these additional details make the difference/similarities and pros/cons more clear. More info is available at these two sites: http://www.professionalsound.com/Catalog/Powermax%20Ultra.htm and

http://remoteaudio.com/meon.htm”  Glen Trew

[Darren]

I think that both of these are great products and I can definitely see where either one may have very definite advantages over the other, depending on one's application.  For example, in my case, the Meon's ability to run one's entire cart through one connection is a definite advantage as my cart already contains it's own internal distribution system and is already set up with one 4 pin XLR connector for the DC input to the entire cart.

What discourages me from purchasing either of these however, is their pricing.

My 32ah system with 15 amps of built in smart charging and a 600 watt sine wave inverter cost under $400 to assemble from individual components and is very compact.

Granted it does not have -all- of the skookum features of the Meon or the Powermax, but it does work perfectly, and has for years.  So, as much as I would like to own one of the above units, I just cannot justify spending that kind of money on my cart's powering.  Please accept my apologies in advance if I am out of line as I'm probably overstepping some sort of boundaries, but I would be curious to know how the price points for these products were arrived at.  Because my feeling is that if they were more affordable, they would find themselves on a much larger percentage of sound carts.

All the best!

Darren

[FSBELLA]

Hey guys,

After reading Gtrews original post again, I think he was referring to the Powermax (not the new ultra) as comparison to the meon??

there both very good products. the end user will not go wrong either way.

Darren,

I do hear that as well sometimes, if the price point was a bit lower (just a little). I really don't know what they cost to manufacture (only PSC & Remote Audio does) but you can imagine that the way both units are built "ford tough" and all the features they BOTH have, the cost must be pretty excessive for all the parts,components and the machinery. especially considering the companies history and the respect of all there products. you get what you pay for, and as stated above, you will not go wrong either way you choose.

[Mick]

I have two power max's, neither of which has a fan or makes any noise whatsoever. They are connected to two 66 amp hour sealed lead acid batteries which are continually charged and which power my cart for over 8 hours when there's no AC. I had them mounted in a custom box with xlr outputs. Although it's heavy it sits on the bottom shelf of the magliner based cart and significantly lowers the center of gravity. I'm very happy with this arrangement and would recommend the power max setup with its variable voltage outputs depending on the xlr pin configuration (6, 12,18)

Cheers

MIck

[davidm]

For the past 10 years or so I have been powering my various system from 2 x15 AH Gel Cells mounted in a Pelican case with smart chargers for overnight charging and more recently with dual 10 amp float chargers on my cart. For the last year this power supply has been struggling to cope with my Mac Mini based Metacorder based cart which draws up to 110 watts. Basically, the poor high current performance of the gel cells results in these relatively small batteries delivering less than 12 volts which quickly causes complaints from most of my audio components.

So instead of investing in some Optima's and larger capacity chargers, in December last year I ordered a Li-Ion based UPS style system from Ocean Server Technology ( www.ocean-server.com ). It's all assembled in a temporary case at the moment but I have put together a dual system each with 4 x 95 watt / 14.4 voltt Li-Ion batteries  and a float charger-controller & 120W /18 volt power supply.  The capacity of the batteries is 52 amps at a nominal 14.4 volts. The 120 W power supplies charge the batteries from flat in about 6 hours while supplying 55 watts each to the cart at 16.5 - 18 volts. When charged the the battery runtime for my cart is around 6.5 - 7 hours on full load with the batteries delivering 16.5 volts full charged and a healthy 13.5  to 14 volts when indicating empty.  I use one of the systems to power the Mac Mini and 15" screen and the other to power the audio equipment.

Ocean Server Technologies have charger controllers which are scaleable so everything from a 1 x 95W Li-Ion Watt battery to over 64 x 95Wt Li-Ion batteries can be built.

These are the components I used:

A95HC-FL SMART LI-ION BATTERY PACK, 95Whr, 14.4V, 6.6Ah, FLYING LEAD

EK-04 UNREGULATED IBPS POWER KIT

LCD DISPLAY w/BACKLIGHT, 2x16 and CABLE

I mounted everything in an old Pelican 1450 case with a low speed 12 volt, 120cm fan running on 5 volts via a DC-dc converter keeping things cool when connected to mains power. I'm looking at putting the parts in a custom aluminum case with passive cooling but I'll need to replace the sealed plastic case mains power supplies with open frame types. There's a few other issues to sort out including installing a 2 way 8 pole on/off switch which will disconnect each of the batteries from the controller board as when the batteries are not being used, there's an approx 1% per day current draw for the controller board and LCD.

A relatively expensive solution but very reliable power and the weight = 10KG / 22 pounds!

David Madigan

Auckland

New Zealand

[Glen Trew]

Glen Trew is a great guy and an asset to this industry.  I look forward to seeing him at the upcoming NAB show and will be the first to buy him a beer...

Hello Ron, and All…

Ron’s points are well received and appreciated. My sentiments for him are the same, and I also look forward to that beer. My comments were not intended to criticize the Powermax, but to illustrate that the previous comparison being made was not necessarily accurate. In doing so, if I misrepresented the abilities of the Powermax, I apologize and am eager to be corrected. At least we will all learn more from a detailed discussion. There is however, still some confusion, possibly on my part, that Ron can clarify…

If the Powermax is powering a cart that uses, what is the total time needed to charge two 33A/hr batteries?

Charge time:

The Powermax has a total of 30A available for charging and/or powering. The specs for  battery-charging current says it is limited to 15A (which would be considered about the safe maximum for a 33A/hr battery). It’s not clear if this is 15A per battery (total of 30A) or a total of 15A for both batteries. A 33A/hr lead acid battery will need about 13A to charge in 2.5 hours. Charging two batteries in 2.5 hours would use 26A, leaving only 4A to operate the cart. If I miss-spoke about the charge time needed for two batteries it is because I assumed the charging current was limited to 15A total so that the remaining 15A would be available for the cart. But if this is, indeed the case, it can only mean that charging two batteries will take twice as long as it takes to charge one, or about 5 hours.

Power available to the cart while charging:

Using similar math: If 15A is being used to charge a Powermax battery, then only 15A remains for the cart, which is less than the Meon always provides to the cart when charging its battery: 30A-15A=15A compared to 18A-0A=18A. No?

If the Powermax always favors the outputs to the cart and provides the remaining current for battery charging, then charge time will increase when cart power goes over 15A. Or, in the case of charging two batteries with 15A each, whenever any current at all is being used for the cart. No?

Anyway, one scenario or the other must be true, unless I am missing something (always a good possibility)

Filters on the DC outlets is another topic worth discussing, as is the inclusion of three different voltages. But in the interest of reasonable length, I’ll defer until another thread. For now, suffice it to say that including these features or not, was an intentional choice of both designs. The philosophy behind the choices made for the Meon is described on the Remote Audio site.

Now, to answer Steve J.’s quibble about the amount of current typically used by a sound cart:

Power requirements are certainly on the increase, and Steve, I’ll be happy if you are correct, but I’ll stand by my comment that the vast majority of sound carts use less than 10A. Also, it was my understanding that the need to replace the earlier Powermax was because, while 14A (the original spec, I believe, was 11A) was sufficient to power a typical cart, it was not enough current to also charge a 33A/hr battery at reasonable speed. Of course, some carts do use more than 10A, but in my observation it is the unusual exception. In fact, I’ll give US$100 to the first person that, in the next 24 hours after this posting is made, can provide a list of just 10 production Sound Mixers anywhere in the world who use more than 18A for their carts in their normal configuration.

Looking forward to learning more,

Glen Trew

[RPSharman]

My AC-powered stuff pull about 12A through an inverter.  The rest of my gear is maybe 5A max.  But I "normally" have a heater on my cart.  My heater draws 7A at 120v in low mode, that's about 70A at 12vDC.  So I count for about 4 or 5 guys.  Feel free to mail me a check for $40 when someone else comes up with the other 6.

[David Waelder]

I don't have a Power Max; I'm working with the older PSC Power Station. My rig is not so power hungry as some others and the Power Station continues to serve my needs. I have used it abroad and can attest that it worked seamlessly with 220 volts. I just acquired a plug adapter - nothing active, just an adapter so the pins fit - and plugged my Power Station into whatever power was available. Everything I powered from the Power Station worked great and the battery charged normally. If it hadn't been for the little bottles of wine with lunch I might have thought I was working in the states. I don't know how the Meon works in a foreign environment but the PSC couldn't have been easier. Well, maybe it could have entered itself on the carnet.

David Waelder

[wolf]

Optima  used to be Gates - chemistry is about the same

http://www.1st-optima-batteries.com/blue_top_battery.asp

weight of lead acids is 1 pound per A/hr at 12V - no getting around that.

The optima can be charged and discharged at much higher currents than the traditional dry lead acids while still having a 300-500 cycle life. I choose Panasonics , they live 6 years, have same cycle life at not too radical discharge rates ( C/5)  and cost less than half of the Optima. Chargers:  the chinese make some good ones now, otherwise its Xenotronics or the 10A and higher ones from West Marine.

I have some slightly used but wired 80 A boxes with great fuses to give away.

we sell 3A  lightweight chinese chargers

Smart Fast Charger (3.0 A) for 12V Lead Acid Battery of 10Ah capacity and up

It features three-stage charging and will charge a lead acid battery quickly without overcharge. Does not get warm.

Do not plug this charger into an inverter powered by a battery!!

Do not charge Batteries that are colder than 32 °F= 0° C

Charge time: 3 Hr for a 7 Ahr Batt., 8 Hr for a 20 Ahr Batt. Inrush current 10A @ 120VAC, at 25oC, AC input voltage 100-240 VAC  freq. 47-63Hz.

$ 95.00 each with 4XLR

and I have one 10 A Xeno noisy fast charger to give away

I have some 10A and 20 A  13.2 V powersupplies  made by Astron to sell cheap as battery float chargers

look at

http://www.wolfvid.com/datasheets/Specials.pdf

( can be kept on batt while on DC)  the fast batt chargers can not be kept on batt while using the batt. V will stay too high and you will burn batt in days.

PSC stuff floats at 13.2 V because of this.

roll your own its such a savings.

wolf  LA soundmixer, video mogul, cynic seeberg

wolfvid.com