|
|||||||||
|
Thread Tools | Search this Thread |
July 10th, 2008, 08:27 AM | #16 |
Inner Circle
Join Date: Dec 2002
Location: Augusta Georgia
Posts: 5,421
|
Dear Cliff,
I found this quote on the Energizer website, under the FAQ's. "In general, fast chargers can limit the NiMH battery lifetime to 150 charges while slower chargers can prolong the cycle life to more than 500 charges"
__________________
Dan Keaton Augusta Georgia |
July 10th, 2008, 08:31 AM | #17 |
Trustee
Join Date: Nov 2005
Location: Sydney Australia
Posts: 1,570
|
NiMH cells are 1.2V compared to Alkaline's 1.5V. That can cause problems with some gear however Sennheiser do supply an optional battery and charger for the G2s that uses 2x NiMH cells so the units should work just fine with 1.2V cells, certainly the 8 that we have do. Due to the lower voltage the indicator on the units may show one bar short of full capacity even with a fully charged battery.
In general the slow chargers are not recommended for high capacity NiMH batteries, the charging logic uses dv/dt and temperature to determine charge status, if you charge them too slowly then the dv/dt might not happen or not be detected and the batteries will be overcharged. NiMH batteries over 2100mAH do self discharge faster however the difference is measured in weeks not days. I think it's Sanyo who first came out with a NiMH cell specifically designed for low self discharge. They're mostly targetted for use in remote controls that draw such little power that the self discharge current would be greater than the current drawn by the device itself. If a G2 is soundy fuzzy running off NiMH cells it's possibly faulty. Try to determine if it's the transmitter or the receiver or even the mic. This kind of fault could easily be overlooked during production testing. I should mention perhaps that the G2 handheld wireless mic will not run off NiMH batteries, it will not even power up however I don't think you can even fit Sennheiser's NiMH battery pack into that unit so it's almost certainly by design. |
July 10th, 2008, 08:31 AM | #18 |
Major Player
Join Date: May 2006
Location: Eugene, Oregon
Posts: 325
|
That makes perfect sense to me - I'll go back to using my standard chargers then and get the batteries today
Bob - I tested the unit with the Alkalines provided in my G2 kit and the mic worked fine so I'm deducing it's the rechargeables causing the problem - these have been left uncharged for a long time and I'm guessing they aren't holding much of a charge. |
July 10th, 2008, 01:43 PM | #19 |
Regular Crew
Join Date: Dec 2007
Location: Kenosha WI
Posts: 65
|
Here's the rub: I can put new, 2750 mah batteries into my R4 and if it powers up, it won't be for long. I can put the same batteries into a Canon 580 flash, discharge at full power and my recycle time is approx. 5 seconds and the batteries will go all day. If I put alkaline batteries in the R4 I am good to go for a few hours. I can repeat the above any day of the week with any rechargeable. Moral of the story: there is most definitely a difference in how some gear responds to or how the rechargeable delivers power to the gear. Given this, why would I want to risk using rechargeable batteries on a shoot? And to tell the truth, I am not sure how much I am "saving" using rechargeables. I can get Duracell Pro alkaline's for .40 a pop. When they won't power my G2, they will power my remotes. We use the rechargables in camera flashes for the short recycle time- but a 10-pack is $25 and they generally last about a year before recycle times diminish and I start all over again.
Anyway, I would not trust rechargables in any of my audio gear. Mike |
July 10th, 2008, 01:49 PM | #20 |
Contributor
Join Date: Jan 2003
Location: Kansas City, MO
Posts: 4,449
|
Apparently Sennheiser trusts them: http://www.bhphotovideo.com/c/produc...e_Battery.html
I've been doing some studio shooting for one of my clients, using their gear, and they have two G2 systems and use rechargeable batteries with no trouble. They're not like the above, but the batteries say "industrial." I guess maybe there's a difference between the cheapo consumer batteries and charger and the heavier duty ones. |
July 10th, 2008, 02:09 PM | #21 |
Inner Circle
Join Date: Dec 2002
Location: Augusta Georgia
Posts: 5,421
|
I have had great success with the Energizer rechargeables.
I follow the rules outlined above. While they are spec'ed as 1.2 volt, they are almost always above 1.38 volts when they come off of a charge cycle. If they have been abused, then the voltage will be lower. I have quite of few sets of Sennheiser G2's, both the regular and the "Plug-On Transmitters", both Series 100 and Series 500. All work extremely well with the Energizers. During very long shoots, over 10 hours, I replace the batteries, if they start to get low, as indicated on the G2's battery gauge. Since I turn them off during breaks, or when a specific actor is not going to act for an hour or so, I very rarely have to replace the batteries on set. I never discharge them all the way. A very knowledgeable person, one who had tested the life of common brands of alkaline batteries stated that the Duracell Pro brand had the lowest capacity of any brand. This was reported as a post on DVinfo.net. Someone else posted that all of his Energizers still work. The only ones that didn’t were the ones he lost. I noticed on the Energizer site that it says not to recharge a cold battery. It will permanently lose capacity. Do what works for you. Energizer rechargeables work well for me.
__________________
Dan Keaton Augusta Georgia |
July 10th, 2008, 04:00 PM | #22 |
Major Player
Join Date: Aug 2007
Location: Austin, TX
Posts: 383
|
hmmm, possibly the quote of the century. ;)
I have been using 2600 mAh Tenergy AA and 250 mAh 9V batteries in my wireless (Zaxcom and Lectros) for several months now and haven't had any issues. I also use a fast charger on both and like Dan points out, you really have to charge them the day/night before to get full use out of NiMH batteries. We burn through a ton of batteries during a shoot where standard Alkalines are used (I've worked with people who refuse to use rechargeable batteries), and I just can't see doing that myself, so when I get the chance, I use rechargeables. Wayne
__________________
Mics: KMR 82 i, NTG-1, MKH418S, MKH8040, SR77, QTC1, QTC40, SR30 Recorder: Zaxcom Deva 5.8 & MIX-12. Wireless: TRX900 stereo, Lectro 411 |
July 10th, 2008, 05:19 PM | #23 | |
Major Player
Join Date: May 2006
Location: Eugene, Oregon
Posts: 325
|
Quote:
I'm going to get a set of the 2700mAh Energizers tonight and give them a whirl and see how they work for me. I was surprised at the Sennheiser battery pack - they're rated 1500mAh which one would think isn't nearly as long lasting as the higher capacity batteries. But then again, I know nothing about this stuff. |
|
July 10th, 2008, 05:43 PM | #24 | |
Trustee
Join Date: Apr 2006
Location: United States
Posts: 1,158
|
Quote:
rechargables have worked fine for me, I run my audio bag off of a pair of 12V 5A paks I had custom made. they run 8-10 hrs with both wireless receivers on, more without, and recharge in a 1/2hr or so. if I powered my rig with 6 9V batteries, even cheap ones at $1.50 each would be $9/day. if you pay more like $3ea, thats $18/day. I did one 10 day straight shoot, that was $90-$180 I didn't spend, and 60 9V batteries that didn't go into the landfill. I'd call that significant. AA's come in a wide variety of quality. another option with the sennheiser paks might be to go to an external battery pak with one extra cell. I've read that some nicads with higher internal resistance can alter the power supply current flow and cause transmitters to act just like you have experianced. I'd try a different set for starters, then call Senn about a warranty exchange because they should work. |
|
July 10th, 2008, 07:27 PM | #25 |
Major Player
Join Date: Dec 2005
Location: Motukarara, New Zealand
Posts: 475
|
i switched from alkaline to rechargeables for my G2s when I discovered sanyo's Eneloop batteries. They have less capacity (although more than i've ever needed for a full day's shoot) but they dont discharge nearly as fast when sitting idle. Where my other rechargeables will drop to like 20% power after a few weeks, the eneloops hold well over 95%... and supposedly will hold up to 90% after a full year.
I gave away all my regular rechargables, bought 40 eneloops, a 10 bay individual cell smart charger and i'm a happy clam. After a shoot I charge up the batteries and put them back in the sound case, confident that they'll be good when I need them. (like alkalines). If i have a critical shoot and have been idle for a month I might stick them back on the charger... but i've had such good luck w/ them that I generally dont. As to the "fuzzy" sound... I'll have to listen closely and see if i can actually hear that. I dont have the greatest ears, but I would think i'd notice something like that. Actually, i have two sets of G2s. maybe I'll put one on alkalines and one on eneloop and record a test for you golden eared freaks out there. cheers! -a |
July 11th, 2008, 07:01 AM | #26 | |
Trustee
Join Date: Nov 2005
Location: Sydney Australia
Posts: 1,570
|
Quote:
|
|
July 11th, 2008, 07:04 AM | #27 |
Inner Circle
Join Date: Dec 2002
Location: Augusta Georgia
Posts: 5,421
|
Dear Bob,
That is great information! I am sure that information will help more than one individual.
__________________
Dan Keaton Augusta Georgia |
July 12th, 2008, 09:43 PM | #28 |
Tourist
Join Date: Jun 2006
Location: Burbank, California
Posts: 4
|
Energizer Lithium
So I went around and around with this when I bought a sennheiser G2 setup 2 years ago. Couldn't figure out where the "fuzziness" was coming from. Finally a friend told me to try the energizer lithium disposables (blue package). Worked perfectly. The trouble with the rechargables was when they started to go, you had no warning. Just suddenly fuzziness 30 minutes into the shoot.
I know it's $9 a shoot, but I can't afford to have the audio go bad, for just $9. |
July 25th, 2008, 10:49 AM | #29 |
Major Player
Join Date: May 2006
Location: Tampa, FL
Posts: 596
|
I purchased eight 2500 mAh Ni-MH batteries online last year. The brand is Merkury. They've always worked well, but I've never really tested them. I charged them, four at a time, in a Panasonic 5-hour Ni-MH charger. each set of four kept my wireless running for over nine hours. (The tested ended because I took my wife out to dinner.)
Fully charged, the meter on both the transmitter and receiver show a full charge and it remained full for an hour. After that it went to two bars (out of three) and remained there for eight hours until I finally left the office. Today they were dead. ;-) So, they lasted between nine and twenty-four hours. I'm guessing closer to nine. These are them: http://www.thomas-distributing.com/m...-batteries.php |
July 25th, 2008, 11:02 AM | #30 |
Major Player
Join Date: May 2006
Location: Tampa, FL
Posts: 596
|
I just found this site - they done some cool comparisons.
http://www.rechargeable-battery-revi...rformance.html Sorting by "Tested Energy," looks like Merkury scores pretty low. The top of the list are Powerex 2700, Ansmann 2700, Ansmann 2800, and Sanyo 2700. And Duracell rates higher than Energizer! Hmmm. And the results... http://www.rechargeable-battery-revi...e-battery.html |
| ||||||
|
|