HELP with Nitecore SRT3 please!!!

[Lomandor]

You forgot a very important feature of this light.

This light accepts AA sized batteries with the extension tube. Given AA NiMh nominal voltage is 1.2V, even if the light has a low voltage cutoff, it will be WAY below your 16340 low voltage protection circuit. The light is probably designed to operate between 0.8v to 4.2v. I seriously doubt the light has battery chemistry detection for different low voltage cutoff for different type of cells.

aau007 Thanks for bringing that to my attention. Though in saying that, both my RCR's, RC123 and 18650's are all 3.7v, so can you explain why these batteries even though they operate around the same voltage, still manage to have a different affect the function of my SRT7. From what I gather, it is NOT the voltage drain that is the issue, but rather the capacity if the battery itself.

 

[aau007]

aau007 Thanks for bringing that to my attention. Though in saying that, both my RCR's, RC123 and 18650's are all 3.7v, so can you explain why these batteries even though they operate around the same voltage, still manage to have a different affect the function of my SRT7. From what I gather, it is NOT the voltage drain that is the issue, but rather the capacity if the battery itself.

I am only referring to the srt3 operating voltage vs low voltage cutoff.
SRT7 is a different beast. It takes single 18650 or two rcr123. Operating voltage can be from 3v to 8.4v. I tried to play with the srt7 to see how the light detects low voltage and trigger the blinking led and could not be conclusive. I think in the srt7 discussion thread, some members brought up the point that the low voltage led blinks in different behavior between using one or 2 cells. You might want to check there.

 

[HaileStorm]

You forgot a very important feature of this light.

This light accepts AA sized batteries with the extension tube. Given AA NiMh nominal voltage is 1.2V, even if the light has a low voltage cutoff, it will be WAY below your 16340 low voltage protection circuit. The light is probably designed to operate between 0.8v to 4.2v. I seriously doubt the light has battery chemistry detection for different low voltage cutoff for different type of cells.

Sorry if I seem a little daft about this but isn't the SRT3 designed to run an rcr123? It's part of the recommended batteries. So shouldnt that mean that the light should give off a warning AT LEAST when using an rcr123 since it was made for that primarily? Forgive me if I'm wrong, I dont really understand the how broad (or not) the light's voltage capacity is. My experience is based on other lights which give off a warning blink to indicate a low voltage battery.

 

[RBWNY]

Sorry if I seem a little daft about this but isn't the SRT3 designed to run an rcr123? It's part of the recommended batteries. So shouldnt that mean that the light should give off a warning AT LEAST when using an rcr123 since it was made for that primarily? Forgive me if I'm wrong, I dont really understand the how broad (or not) the light's voltage capacity is. My experience is based on other lights which give off a warning blink to indicate a low voltage battery.

I have many many different lights, from all the major brands, using all the popular cell sizes. I can't actually say that ANY of the lights give a low-battery warning (as you're describing it). In MOST cases, the protection circuit from the battery will shut the light off before reaching a dangerously low voltage. I honestly cannot understand what your issue is with this. As long as you're using protected RCR's, it'll shut off when it gets close to 3v. Admittedly that's not an ideal scenario to keep your cells fresh...I understand that, and in my 1 cell RCR lights this happens frequently because I forget how often I've used it after a battery charge and keep forgetting to check the voltage. One or two of my lights will start "acting up" when the battery charge gets low, but I've never thought of this as being an intended "warning". The 4sevens Malestrom will flicker when changing modes. The Zebralight SC600 will shut-off if it's switched on high. But these two are the exceptions. Most any other light...(except for a AA light) won't think twice to leave me in the dark when the cell decides to say night-night.

 

[Lomandor]

I am only referring to the srt3 operating voltage vs low voltage cutoff.
SRT7 is a different beast. It takes single 18650 or two rcr123. Operating voltage can be from 3v to 8.4v. I tried to play with the srt7 to see how the light detects low voltage and trigger the blinking led and could not be conclusive. I think in the srt7 discussion thread, some members brought up the point that the low voltage led blinks in different behavior between using one or 2 cells. You might want to check there.

Not really! The only difference between the SRT7 and the SRT3 is that Charlie put the SRT7 thru the chocolate bar miniaturising machine at the Wonka factory and there so came to light the SRT3!! True story...
Look, I'm pretty new at this stuff and not an old timer like you. Though that said, I don't need to check another thread to see what my SRT7 is doing. It is clear to me that the SRT7 will work according to factory specks on 18650's and CR123's which are both larger capacity than a RCR123.
So if a primary (CR123) is used in the SRT3 (which have a much larger capacity than a RCR123) instead of an RCR123, he might, just might not have the problem. Why, I don't know, but that's what is happening. If you check the specks, NOWHERE does it say compatible with RCR's, just primaries. So next time you pull your hair out, and your torch apart with your fingers and toes, loosing sleep, searching for answers, just read the manual. Just saying......

 

[aau007]

Not really! The only difference between the SRT7 and the SRT3 is that Charlie put the SRT7 thru the chocolate bar miniaturising machine at the Wonka factory and there so came to light the SRT3!! True story...
Look, I'm pretty new at this stuff and not an old timer like you. Though that said, I don't need to check another thread to see what my SRT7 is doing. It is clear to me that the SRT7 will work according to factory specks on 18650's and CR123's which are both larger capacity than a RCR123.
So if a primary (CR123) is used in the SRT3 (which have a much larger capacity than a RCR123) instead of an RCR123, he might, just might not have the problem. Why, I don't know, but that's what is happening. If you check the specks, NOWHERE does it say compatible with RCR's, just primaries. So next time you pull your hair out, and your torch apart with your fingers and toes, loosing sleep, searching for answers, just read the manual. Just saying......

You are assuming the srt7 and srt3 circuit are same? I don't think so. At the very least, srt3 has a boost/buck circuit and srt7 only has a buck circuit. This is a srt3 thread and I don't believe it is appropriate to start discussing srt7 here and hijack the OP's thread.

 

[Lomandor]

I tried to play with the srt7 to see how the light detects low voltage and trigger the blinking led and could not be conclusive.

Hmmm, hijacking?

if a primary (CR123) is used in the SRT3 instead of an RCR123, he might, just might not have the problem. If you check the specks, NOWHERE does it say the SRT3 is compatible with RCR's, just primaries.

NOT Hijacking! Just trying to give him the solution to his problem WITH the SRT3. Read the manual! Just saying....

 

[aau007]

So if a primary (CR123) is used in the SRT3 (which have a much larger capacity than a RCR123) instead of an RCR123, he might, just might not have the problem. Why, I don't know, but that's what is happening. If you check the specks, NOWHERE does it say compatible with RCR's, just primaries. So next time you pull your hair out, and your torch apart with your fingers and toes, loosing sleep, searching for answers, just read the manual. Just saying......

Not sure if the link will be removed by mod but here is the pdf manual directly from nitecore's web site. rcr123 is listed as "Recommended".
http://www.nitecore.com/UploadFile/Files/download/1-1_SRT3_UM_EN.pdf

Also on nitecore's web site about srt3 product details, rcr123 is listed as THE battery to use to achieve the max 550 lumens. Using cr123 primariy will only get to 330 lumens according to nitecore.
http://www.nitecore.com/productDetail.aspx?id=87

So read the manual and make sure you read the right manual.

 

[passive101]

My SRT3 runs on a RCR123 rechargeable without problems.

 

[Lomandor]

Not sure if the link will be removed by mod but here is the pdf manual directly from nitecore's web site. rcr123 is listed as "Recommended".
http://www.nitecore.com/UploadFile/Files/download/1-1_SRT3_UM_EN.pdf

Also on nitecore's web site about srt3 product details, rcr123 is listed as THE battery to use to achieve the max 550 lumens. Using cr123 primariy will only get to 330 lumens according to nitecore.
http://www.nitecore.com/productDetail.aspx?id=87

So read the manual and make sure you read the right manual.

Bahaha hahaha! Took you long enough to check it up..

 

[aau007]

Bahaha hahaha! Took you long enough to check it up..

I had always known. Just never had time to pull the links. Besides, you kept asking to read the manual + say "NOWHERE does it say..." Not sure if you are just trying to pull a fast one on the OP.

 

[HaileStorm]

Why, I don't know, but that's what is happening. If you check the specks, NOWHERE does it say compatible with RCR's, just primaries. So next time you pull your hair out, and your torch apart with your fingers and toes, loosing sleep, searching for answers, just read the manual. Just saying......

The manual IS the first place I checked. I wouldn't have posted here otherwise. And here's a portion of the srt3 manual that I snapped:

 

[aau007]

Hail,

I don't believe there is a low voltage cutoff for rcr123 battery but I could be wrong. When your battery protection circuit cuts in, the light turns off and you click it off. Without load, the battery voltage will recover and when you click it a little later the light turns on. Depending on how low the battery is and how much voltage has recovered, the subsequent on time will differ. However, given the battery will get lower and lower, you on time will become less and less until maybe it only blinks. At the same time, the time it takes for the light to be able to light up is lengthen as it needs more time for the voltage to recover.

There are a few ways you can find out definitively.
1. Using a linear power supply, set it at like 2A CC and 4V. Tap it to the light and set light at max. Slowly adjust the voltage down and see when the light will cut out. Then set at 3.1V and do the same. Then set at 1.5V and do the same.
2. Find an unprotected 3.7V rechargeable battery. Remove the head of the light and using wires/clips, etc and a battery carrier, tap the battery directly onto the light. Set the brightness to higher than medium and put a DMM on the battery. Watch the voltage drops. If it drops too fast, lower the brightness. Let the voltage continue to drop and see if the light will turn off. If the light does not turn off as the voltage drops below 2.7V, you can manually disconnect the battery to protect it or you can let it drain to the point you are convinced that the light does not have a low voltage cutoff. Below 2.5V, you are likely to damage the battery. I onced dropped the voltage on a unprotected lithium to 0V and took me quite a while to revive it but that was just luck.
3. CAUTION: doing this may (and likely will) ruin your battery so only do this test if you are willing and can afford to have one of your batteries kiss you goodbye. Put an unprotect rcr123 or cr123 in the light, turn it on to like at least med. Leave the light on until it turns off by itself, then leave the light alone for at least a few more days at that on setting. After a few days, take the battery out and measure the voltage. If your battery voltage is below 1V, then no low voltage cutoff in the light.

 

[HaileStorm]

Hail,

I don't believe there is a low voltage cutoff for rcr123 battery but I could be wrong. When your battery protection circuit cuts in, the light turns off and you click it off. Without load, the battery voltage will recover and when you click it a little later the light turns on. Depending on how low the battery is and how much voltage has recovered, the subsequent on time will differ. However, given the battery will get lower and lower, you on time will become less and less until maybe it only blinks. At the same time, the time it takes for the light to be able to light up is lengthen as it needs more time for the voltage to recover.

There are a few ways you can find out definitively.
1. Using a linear power supply, set it at like 2A CC and 4V. Tap it to the light and set light at max. Slowly adjust the voltage down and see when the light will cut out. Then set at 3.1V and do the same. Then set at 1.5V and do the same.
2. Find an unprotected 3.7V rechargeable battery. Remove the head of the light and using wires/clips, etc and a battery carrier, tap the battery directly onto the light. Set the brightness to higher than medium and put a DMM on the battery. Watch the voltage drops. If it drops too fast, lower the brightness. Let the voltage continue to drop and see if the light will turn off. If the light does not turn off as the voltage drops below 2.7V, you can manually disconnect the battery to protect it or you can let it drain to the point you are convinced that the light does not have a low voltage cutoff. Below 2.5V, you are likely to damage the battery. I onced dropped the voltage on a unprotected lithium to 0V and took me quite a while to revive it but that was just luck.
3. CAUTION: doing this may (and likely will) ruin your battery so only do this test if you are willing and can afford to have one of your batteries kiss you goodbye. Put an unprotect rcr123 or cr123 in the light, turn it on to like at least med. Leave the light on until it turns off by itself, then leave the light alone for at least a few more days at that on setting. After a few days, take the battery out and measure the voltage. If your battery voltage is below 1V, then no low voltage cutoff in the light.

Very useful info, thanks for this. Will head out to buy a cr123 primary and likely do test #3. I did try draining a 2000mah eneloop with the light. Left it on high and waited for it to die. When the battery was about to die, the light just flickered randomly. No low battery blinking indicator like my predator and no pulsing like my klarus to likewise indicate a dying battery. Would that be considered the same as test #3? I tried using the same eneloop on a 1xaa light and it was very dim so I think the eneloop was indeed low on power...

 

[HaileStorm]

My SRT3 runs on a RCR123 rechargeable without problems.

Mine doesn't have problems running on rcr123s either but it's my first light which costs more than $50 that doesn't have a low battery indicator which led me to think that the light was defective.

Does yours indicate you when the battery is low? Or does it also just shuts off? Im using the suggested 650mah nitecore rcr123...

 

[aau007]

Very useful info, thanks for this. Will head out to buy a cr123 primary and likely do test #3. I did try draining a 2000mah eneloop with the light. Left it on high and waited for it to die. When the battery was about to die, the light just flickered randomly. No low battery blinking indicator like my predator and no pulsing like my klarus to likewise indicate a dying battery. Would that be considered the same as test #3? I tried using the same eneloop on a 1xaa light and it was very dim so I think the eneloop was indeed low on power...

If it flickers randomly, it is usually a sign of NO low voltage cutoff. The battery voltage has gone low enough under load that the circuit is not getting enough voltage to keep the LED lit. As the LED goes on/off, the battery is undergoing load/no load situation, causing the voltage to fluctuate and that effect causes the LED to randomly flicker. The question now is whether there is a low voltage cutoff between 1.8V to 2.5V or so for when you use cr123 or rcr123. This will require the circuit to detect the initial ON voltage and switch on a low voltage cutoff feature, if any, which I seriously doubt. It makes the circuit more complicated.

 

[HaileStorm]

I've tried draining my rcr123 again and left the light on. Same thing happened, the light just shut off. I then proceeded to remove the battery and put it in my other light. After a couple of seconds, the light just shut off too. I've never encountered a battery's protection circuit kicking in, but it seems like that's what happened. So i guess it's safe to say that the my srt3 is free from defects?

 

[dc38]

I've tried draining my rcr123 again and left the light on. Same thing happened, the light just shut off. I then proceeded to remove the battery and put it in my other light. After a couple of seconds, the light just shut off too. I've never encountered a battery's protection circuit kicking in, but it seems like that's what happened. So i guess it's safe to say that the my srt3 is free from defects?

Make sure that when doing these tests, always record at least the cell voltage. That will help when we try to figure out what is going on. Also, my intuition compels me to ask...was the majority of your usage with 16430 in max brightness mode? If so, how long did you run it for, and how hot did it get?

 

[HaileStorm]

Make sure that when doing these tests, always record at least the cell voltage. That will help when we try to figure out what is going on. Also, my intuition compels me to ask...was the majority of your usage with 16430 in max brightness mode? If so, how long did you run it for, and how hot did it get?

I'm assuming that it's the protection of the cell kicking in. When I tried draining it on high mode, it shut off at 3.0v. Got pretty warm so I put it next to a fan. I turned it on again, this time draining it on medium, it cut off at 2.7v. When I put the battery in my other flashlight, same thimg happened. It just turned off so I really think that it's the battery protection.

 

[dc38]

I'm assuming that it's the protection of the cell kicking in. When I tried draining it on high mode, it shut off at 3.0v. Got pretty warm so I put it next to a fan. I turned it on again, this time draining it on medium, it cut off at 2.7v. When I put the battery in my other flashlight, same thimg happened. It just turned off so I really think that it's the battery protection.

It was protection....my protected aw cuts at 2.9v on max as well