Night Vision PVS1531 + COTI Battery Issues (with and w/o battery pack)

[NHPiper]

So I have one of the L3 sets of PVS1531 goggles. Always had short battery life, like 1-2ish hours max. One time when I was out I swapped 3 batteries in 15 minutes. Come to find out, I haven’t been using lithium AA’s, just regular alkaline. @WillHugh had had no problem with his and a quality lithium AA (Energizer Ultimate Lithiums),

So I decided to get a PVS31 battery pack, COTI, and Y cable. I popped some of the cheaper AAs in the battery pack and immediately got a low battery indicator on the 1531s. So I swapped in Duracell Optimums and got maybe 3 hours before the battery light came on. I ran a COTI at the same time for at least half the time.

Anyone else having the same issue? I talked with @SierraLima who said he heard about conversations with Saffron/L3 about the Y cable stating it wasn’t meant to power goggles and a COTI at the same time. Seems odd to me and I know others who haven’t had a problem running PVS31 and the COTI at the same time.

Ordered some Lithiums to try tomorrow so hopefully that fixes it!

@SkyScrapin or @TheHorta have any similar issues?

 

[CoryT]

Lithiums have a different power profile than alkaline, providing high voltage under load where it remains until they pretty much drop dead. The alkalines have a curved profile and voltage drops off earlier under load and continues to fall until dead. That's an issue with high current draw devices, like the tubes in NVG's. Absolutely use the lithium's, which will also perform better in cold weather and have a better shelf life.

 

[Jong]

Where do you get this Y cable?

 

[TheHorta]

I’ve only ever used Energizer Lithiums in all my NV/Thermal gear. I only have 31A’s, but since they use the same pack/cable I assume the power consumption should be the same.

I’m still on the original set of lithiums in the two sets of 31A’s that I own. You should get at least 24-30 hours on a fresh set of 4.

 

[jwramp]

Is the Y cable box where it splits from one cable to two getting hot when plugged in?

 

[NHPiper]

Is the Y cable box where it splits from one cable to two getting hot when plugged in?

Good question will have to test tonight!

 

[NHPiper]

Where do you get this Y cable?

I picked mine up from a member. Either @Choid or @SierraLima may have spares to offload.

 

[Choid]

I have one more. Hit me up if you are interested.

 

[SierraLima]

Can anyone confirm if the current draw is sufficient to power both a pas-29a and a set of goggles? I had a discussion with a guy on a different board who said the pack wasn't supposed to power both at the same time. It doesn't make sense but also understand maybe the Amp draw is too much for a 31 battery pack

 

[NHPiper]

Curious about @SierraLima's intel as well.

The lithium batteries will be here tonight so i will get out to see if they provide the more stable amp output to fix the issue.

 

[SkyScrapin]

@NHPiper Sorry, no experience with the 1531. I'm eagerly awaiting for them to arrive.

 

[JonLSU]

Supposedly w the 1531s and the batt pack, you get 40 to 50 hours on lithiums. I’m at about 30 hours and still going strong. I don’t put a battery in the unit.
No clue on the splitter situation

 

[NHPiper]

Bad news gents....

The battery pack with quality lithium batteries CANNOT run the 1531 and COTI at the same time. Within 10 minutes i got the blinking red light in the goggles before they died. So frustrating, I mean that is the whole point of a battery pack and splitter cable!!

Is anyone with PVS31 goggles running into this issue? Could it be my splitter cable?

I am going to call L3 tomorrow and try to get some info. I guess worst case i just use the cord to power the COTI since a quality lithium in the goggles should run plenty of battery life, unless something is wrong with the goggles.

 

[SierraLima]

Thats what I was told, after 10minutes the devices will shutdown. I would guess the main purpose then is to be able to route the cable securely or inside the helmet and not need to remove to swap cables depending on coti use or purely goggles.

Just the goggles should run longer than a night cycle on lithiums according to TNVC. So I guess it the goggles went down you could swap cables instead of changing a battery to get nvgs working again.

 

[WhereNow&How]

Bad news gents....

The battery pack with quality lithium batteries CANNOT run the 1531 and COTI at the same time. Within 10 minutes i got the blinking red light in the goggles before they died. So frustrating, I mean that is the whole point of a battery pack and splitter cable!!

 

[WhereNow&How]

It sounds like you are having a really bad issue trying to power both. In the article below they are saying you should be getting about 11 hours.

Bad news gents....

The battery pack with quality lithium batteries CANNOT run the 1531 and COTI at the same time. Within 10 minutes i got the blinking red light in the goggles before they died. So frustrating, I mean that is the whole point of a battery pack and splitter cable!!

The COTI is not very efficient with power consumption. It will deplete a CR123 in just a couple of hours of continuous use. If you use that cable above to power the COTI with a PVS31 the battery pack goes from an average 50 hours run time down to just 11 hours.

FRIDAY NIGHT LIGHTS: COTI (Clip-On Thermal Imager) -

On this week's FNL, we take a look at COTI. Clip-On Thermal Imager is a small portable device that overlays thermal into a night vision device.

www.thefirearmblog.com

 

[NHPiper]

It sounds like you are having a really bad issue trying to power both. In the article below they are saying you should be getting about 11 hours.




The COTI is not very efficient with power consumption. It will deplete a CR123 in just a couple of hours of continuous use. If you use that cable above to power the COTI with a PVS31 the battery pack goes from an average 50 hours run time down to just 11 hours.

FRIDAY NIGHT LIGHTS: COTI (Clip-On Thermal Imager) -

On this week's FNL, we take a look at COTI. Clip-On Thermal Imager is a small portable device that overlays thermal into a night vision device.

www.thefirearmblog.com

I'm really curious if he actually tested that to see if he got 11 hours.

 

[rct4694]

How much battery life are you getting with a quality lithium battery in the 1531 itself? I’ve been told with 31’s not to use alkaline batteries because the unit will develop a kind of battery memory. I have seen several sets that had a significantly lower runtime(even with lithium’s) and this is what we believed the culprit was.

 

[NHPiper]

How much battery life are you getting with a quality lithium battery in the 1531 itself? I’ve been told with 31’s not to use alkaline batteries because the unit will develop a kind of battery memory. I have seen several sets that had a significantly lower runtime(even with lithium’s) and this is what we believed the culprit was.

God I hope that isnt the case. I didnt run lithiums to start, just swapped over. Cant confirm the amount of life I am getting yet with them. Wondering if they should go back to L3 for inspection.

I chatted with Nick, the guy who did the Friday Night Lights review posted above and he has no issues powering both his units. Wondering if he got lucky.

 

[Dvlray6]

My pvs31a and splitter for the e coti are on the way. I’ll let you know what kind of run time I get.

 

[B21TLB]

God I hope that isnt the case. I didnt run lithiums to start, just swapped over. Cant confirm the amount of life I am getting yet with them. Wondering if they should go back to L3 for inspection.

I chatted with Nick, the guy who did the Friday Night Lights review posted above and he has no issues powering both his units. Wondering if he got lucky.

The battery indicator is calibrated to L91 lithium batteries. The system is designed to run on the L91. The different discharge rates of the batteries effect how long the unit runs due the programing. If you have questions, call the number listed in the operators manual. You will get a call back, it may take a little bit but they will respond.

 

[NHPiper]

The battery indicator is calibrated to L91 lithium batteries. The system is designed to run on the L91. The different discharge rates of the batteries effect how long the unit runs due the programing. If you have questions, call the number listed in the operators manual. You will get a call back, it may take a little bit but they will respond.

Unfortunatelt I think the Energizer Ultiumate Lithiums are L91, so they run fine in the goggles but not in the battery pack.

Could be the colder temps right now in NH.

 

[NHPiper]

So the update from the manufacturers I received was that the draw power on the thermal is 10 times higher than that of goggles. For that reason, even with a quality battery pack and splitter cable, you will most likely not be able to run goggles and COTI at the same time. They said that the ECOTI will make this worse.

 

[WhereNow&How]

So the update from the manufacturers I received was that the draw power on the thermal is 10 times higher than that of goggles. For that reason, even with a quality battery pack and splitter cable, you will most likely not be able to run goggles and COTI at the same time. They said that the ECOTI will make this worse.

Well so much for the OEM's ability to correctly design a system that our guys overseas are betting their lives on.

That sucks.

And to think they charge around $1,250 and north of that for the system.

 

[TheHorta]

This post specifically caused me to spend the last 3 days running a brand new set of 2376 31A’s and a 29A COTI using a fresh set of 4 Energizer Ultimate Lithiums with the standard 31A battery pack and the 31/COTI splitter cable.

I was able to get 4 hours and 22 minutes on the fresh set before complete power down.

 

[SierraLima]

Horta, did the coti stay in external power supply or did it cycle to an internal battery any? (If a cr123 was in the coti)

 

[WhereNow&How]

Horta, did the coti stay in external power supply or did it cycle to an internal battery any? (If a cr123 was in the coti)

Excellent question.

Eagerly awaiting Horta's answer as well.

 

[NHPiper]

Horta, did the coti stay in external power supply or did it cycle to an internal battery any? (If a cr123 was in the coti)

They should auto default to the external power as soon as they are connected. If you got that kind of life I would be curious what @TheHorta is using for lithium batteries so i can try as well. I dont think it is a battery pack issue, the one I got looks brand new.

Also curious since those were PVS31A goggles if the PVS1531 are more sensitive to current or voltage, maybe because they use different tubes?

The guy I talked with who is working on the design of a new battery and cable for the eCOTI and did say that the cable for the COTI may not be able to handle the current, hence why they are redesigning for the ECOTI.

 

[NHPiper]

Well so much for the OEM's ability to correctly design a system that our guys overseas are betting their lives on.

That sucks.

And to think they charge around $1,250 and north of that for the system.

Agreed. But to my comment above, there may be different power draws on the PVS31 vs PVS1531.

 

[WhereNow&How]

The guy I talked with who is working on the design of a new battery and cable for the eCOTI and did say that the cable for the COTI may not be able to handle the current, hence why they are redesigning for the ECOTI.

Can you find out from your guy what the milliamp draw is on the Pas 29A Coti.

 

[NHPiper]

Can you find out from your guy what the milliamp draw is on the Pas 29A Coti.

I can try!

 

[WhereNow&How]

Agreed. But to my comment above, there may be different power draws on the PVS31 vs PVS1531.

Good point, but realistically it should not be that much of a difference I would think as NV sips power compared to the power guzzling thermals.

 

[TheHorta]

No internal batteries on either the 31’s or COTI.

 

[WhereNow&How]

No internal batteries on either the 31’s or COTI.

So a good quality CR123 in the COTI might (best case scenario 70 degree Fahrenheit) give you 2 hours run time before that annoying as hell warning light comes on in your COTI that you probably got less than 30 minutes remaining.

So by my chypering (2 hrs 30 min + 4 hrs 22 min) it looks like say approximately 7 hrs run time on the COTI max.

Not exactly a long runtime on a COTI for $1250 bucks.

 

[NHPiper]

So a good quality CR123 in the COTI might (best case scenario 70 degree Fahrenheit) give you 2 hours run time before that annoying as hell warning light comes on in your COTI that you probably got less than 30 minutes remaining.

So by my chypering (2 hrs 30 min + 4 hrs 22 min) it looks like say approximately 7 hrs run time on the COTI max.

Not exactly a long runtime on a COTI for $1250 bucks.

Maybe if you are running that as a standalone unit plugged into the battery pack. Running both together I can't get 10 minutes on the goggles. Haven't had a chance to test the time I get on the COTI with just it plugged in, but likely heading out in the next 72 hours for a couple of hours in 40F weather, so I will let it run the whole time to see what happens.

I heard that with a battery pack, goggles, and the ECOTI, the whole system wasn't getting more than 2 hours in warm weather. I would hope the COTI is slightly longer since it is running at a lower processing speed than the newer system.

Wondering if the GPNVG pack with CR123 batteries would be the better option? Anyone have any thoughts? The current BNVD battery packs with the Y cable seem to have hit or miss performance.

 

[WhereNow&How]

@NHPiper. That really sucks. You would think the powers that be would design a system to run at least 12 hours with both units for at least 1 complete night of darkness, especially for the whopping price they are charging.

 

[WhereNow&How]

Maybe a miniaturized nuclear power generator is the answer. Wonder what that's gonna cost.

 

[NHPiper]

@NHPiper. That really sucks. You would think the powers that be would design a system to run at least 12 hours with both units for at least 1 complete night of darkness, especially for the whopping price they are charging.

Agreed wholeheartedly.

 

[NHPiper]

So I left a message for Optics1 on a long shot because their office is about a mile from my office, and one of their guys called me back! We're going to schedule time in the next week or so for me to meet up with them so they can test all of my equipment and figure out where the actual issue is. They said one other guy had reached out to them and L3 gave them the run-around when they directed them back to L3, so they were willing to dive in and figure out what the root cause of the issue was!

Talk about sweet customer service!

 

[Dvlray6]

So I left a message for Optics1 on a long shot because their office is about a mile from my office, and one of their guys called me back! We're going to schedule time in the next week or so for me to meet up with them so they can test all of my equipment and figure out where the actual issue is. They said one other guy had reached out to them and L3 gave them the run-around when they directed them back to L3, so they were willing to dive in and figure out what the root cause of the issue was!

Talk about sweet customer service!

You have my interest as I have PVS31a on the way and already have the e-coti here. I have the cable on the way. I want one source of power for these things.

 

[WhereNow&How]

I want one source of power for these things.

These work well day or night. Never run out of power.

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Amazon.com : K-TOR Power Box 20 Watt Pedal Generator, Can Charge a 12 Volt Battery, Bundled with Cree Rechargeable Flashlight with Integrated USB : Garden & Outdoor

www.amazon.com

 

[NHPiper]

You have my interest as I have PVS31a on the way and already have the e-coti here. I have the cable on the way. I want one source of power for these things.

When are the 31s due in? Curious if they have a different current draw than the 1531s. Feel free to send them to me for testing

 

[WhereNow&How]

We're going to schedule time in the next week or so for me to meet up with them so they can test all of my equipment and figure out where the actual issue is. They said one other guy had reached out to them and L3 gave them the run-around when they directed them back to L3, so they were willing to dive in and figure out what the root cause of the issue was!

You the man for sure.

 

[NHPiper]

You the man for sure.

Ironically someone else from their company responded to the email inquiry I also submitted and said the battery pack and cable weren't designed to run both. So it sounds like it may be hit or miss. Regardless, appreciate their willingness to look into it further. Hope they can schedule some time with one of their engineers next week at the latest.

 

[WhereNow&How]

Ironically someone else from their company responded to the email inquiry I also submitted and said the battery pack and cable weren't designed to run both. So it sounds like it may be hit or miss. Regardless, appreciate their willingness to look into it further. Hope they can schedule some time with one of their engineers next week at the latest.

That is wild. Who would have thought that.

Seems to me, the easy solution would have been an adequately sized Anker style rechargeable 5 Volt battery that could easily run both for 12 hours minimum. All they have to do is put a buck 5 Volt to 3.2 Volt step down regulator on the cable and a USB fitting to plug into a rechargeable USB battery.

Thermal manufacturers in general have offered some pretty poor solutions to power their devices in the past. Kinda like it was an afterthought for them.

 

[NHPiper]

Meeting with some of the Optics 1 engineering team on Monday. Stay tuned!

 

[NHPiper]

Met with the guys at Optics 1 yesterday! They didn't realize that I have a set of pvs-15 31 goggles, they thought they were the 31 goggles. Apparently they've had a really hard time getting their hands on a set of 1531 goggles to build a new bracket the housing for the thermal units too. So I basically traded them my goggles in return for them doing some R&D to figure out what's going on and also give me one of their brackets that they develop.

Their initial reaction is at the issue that's presenting itself is the result of the Y cable. There is a box on the cable that is essentially a power converter so they're going to pull it apart and make sure that it's splitting the current correctly. They basically said that they would fix it or replace it! That came straight from one of their top engineers and business development guys.

According to them, with the older COTI model there should be no issue getting 12 plus hours even in cold weather running both the goggles and the thermal. The ECOTI is another story entirely. Both they and at least one third-party I know are working on the development of new battery packs and power cables because the military is not even getting two hours running both thermal and goggles together.

One interesting point is that because the housing is so wide on the 1531, the Imager will not line up with the center of your I2 night vision tube. For those of us who aren't kicking in doors that's probably not a big deal. You'll just want to make sure that it's mounted at the 6 o’clock position, versus horizontal, so that the projected image is fairly close to Centerline. The ECOTI has the ability to swap the height of the image head, so this isn't as much of an issue as the older COTI.

I'm supposed to hear back today from them so that they can confirm what the issue is with the battery pack and cable power in both systems. Stay tuned for more info.

 

[WhereNow&How]

Met with the guys at Optics 1 yesterday! They didn't realize that I have a set of pvs-15 31 goggles, they thought they were the 31 goggles. Apparently they've had a really hard time getting their hands on a set of 1531 goggles to build a new bracket the mouth of the thermal units too. So I basically traded them my goggles in return for them doing some R&D to figure out what's going on and also give me one of their brackets that they develop.

Their initial reaction is at the issue that's presenting itself is the result of the Y cable. There is a box on the cable that is essentially a power converter oh, so they're going to pull it apart and make sure that it's splitting the current correctly. They basically said that they would fix it or replace it! That came straight from one of their top engineers and business development guys.

According to them, with the older COTI model there should be no issue getting 12 plus hours even in cold weather running both the goggles and the thermal. The ECOTI is another story entirely. Both day and at least one third-party I know are working on the development of new battery packs and power cables because the military is not even getting two hours running both thermal and goggles together.

One interesting point is that because the housing is so wide on the 1531, the Imager will not line up with the center of your I2 night visiom tube. For those of us who aren't kicking in doors that's probably not a big deal. You'll just want to make sure that it's mounted at the 6 position, versus horizontal, so that the projected image is fairly close to Centerline. The ECOTI has the ability to swap the height of the image head, so this isn't as much of an issue as the older COTI.

I'm supposed to hear back today from them so that they can confirm what the issue is with the battery pack and cable power in both systems. Stay tuned for more info.

That is really good info. Much appreciated. Keep us updated please.

 

[NHPiper]

One other thing that I forgot to mention is that they were pretty clear that mounting the thermal units on the focus ring of any goggle is not ideal. It puts the imager much farther out than they spec for. You want to have it much closer to the actual objective lens, or you risk some degree of image degradation. Their solution for the 1531 bracket will hopefully fix this on those housings.

 

[WhereNow&How]

One other thing that I forgot to mention is that they were pretty clear that mounting the thermal units on the focus ring of any goggle is not ideal. It puts the imager much farther out than they spec for. You want to have it much closer to the actual objective lens, or you risk some degree of image degradation. Their solution for the 1531 bracket will hopefully fix this on those housings.

Yeah, I remember my back and forth with one of the (so say) SME on this issue when he said it was fine to mount to the focus ring.

I guess what Optics 1 had to say about that, vindicates my back and forth with SME.

I sure hope he reads your post on what Optics 1 had to say.