Surefire EDCL1-T

[fyrstormer]

Mine works with a 4.2V battery also. Though interestingly, if I use a protected cell it won't engage high-mode, only low-mode. It doesn't even flicker when I try to use high-mode; it just continues to run in low mode. Unprotected cells work as expected.

 

[Vox Clamatis in Deserto]

Mine EDCL1-T is absolutely OK with a 4.2V battery.

Mine works with a 4.2V battery also. Though interestingly, if I use a protected cell it won't engage high-mode, only low-mode. It doesn't even flicker when I try to use high-mode; it just continues to run in low mode. Unprotected cells work as expected.

​

My older light works fine with a battery hot off the charger at 4.2 volts, although the protected Li-ion cells shut down much faster on high than the IMR batteries.

There seems to be something changed in the recent units.:thinking:

 

[fyrstormer]

I wonder if the driver is detecting relative voltage sag, and switching to low-power mode when the voltage drops a certain percentage compared to the initial voltage at the moment of power-on, rather than detecting the absolute voltage of the battery.

 

[Vox Clamatis in Deserto]

Re: Surefire EDCL1-T Runtime Tests

After taking a look at my post on this thread from earlier in the year, it looks like I also had the low mode only results from a Fenix rechargeable cell:

I like to use rechargeable batteries whenever possible and save my CR123A's for backup and Y3K. A Fenix RCR123A in the drawer would only power the light in low mode. No load voltage on the Fenix cell was still about 4.0 after the test so I'm thinking the problem is a voltage drop due to the high current draw. I charged the Fenix cell to 4.2 volts and still got only low mode.

Surprisingly, an old AW RCR123A runs the light fine on high power for several minutes before going dark. Cycling the power allows the light to come back on for a while longer.

I put an unprotected Exell IMR 16340 in the -1T. After 25 minutes on high the light dimmed visibly (but would still switch between high and low) and at 35 minutes it started to flicker. At that point I discontinued the test and the battery read 2.12 volts when put into the Nitecore D4 charger. That's lower than I like to run even an IMR but it is good to know that the EDCL-1T has a nice tail of usable light as the battery depletes.

As with the EDCL-2T and E1B-MV, it looks to me like IMR cells are the way to go if you want to use rechargeable batteries on this high current draw light.

I've used both protected and unprotected IMR cells in the EDCL-1T since those initial tests and have not had a problem.

I rummaged around in the drawer and found a Fenix ARB-L16-700 lithium-ion cell and charged it to 4.2 volts with a Nitecore charger. Once again, I only got low mode on the EDCL-1T. A similar Olight ORB-163P06 cell gives high and low mode but abruptly shuts down after about three minutes on high. And, as before, the Olight protected IMR cell ORB-163CO5 runs on high for about half an hour before suddenly going dark.

Maybe there is no change in the recent lights and these differing results we get are from variations in our individual units. Perhaps 4.2 volts at a high current draw is an edge case for a light designed to consume disposable (and profitable for SF :naughty:) lower voltage CR123A's.

In the era of the SureFire U2 folks here used to wax poetic about the boost and buckwheat driver circuits. From an EB1 teardown I did years ago it appears that the electronics in the head have a microcontroller and high parts count. Does the voltage sag with some cells signal the driver to go to low mode since it thinks the resistor in the tactical tailcap is in the circuit? Anyway, in my experience some rechargeable batteries work well in this light, others do not.

 

[fyrstormer]

Re: Surefire EDCL1-T Runtime Tests

My understanding is the resistor doesn't "signal" the driver to do anything, it just obstructs amperage flow from the battery so the driver can't run at full power. A constant-voltage driver will adjust as necessary to produce the specified output voltage, allowing the output amperage to droop instead, whereas a constant-current driver will attempt to ramp-up its output voltage until it either has enough output voltage to push the specified amperage or until it drops out-of-regulation entirely because it exceeds its operational capabilities. In that respect, a weak battery would produce the same effect. I'm surprised that a protected RCR123 would have this problem, but I can't argue with my own personal experience. I mean, I've got brain problems, but they're not that bad. :laughing:

 

[J_C_S]

Re: Surefire EDCL1-T Runtime Tests

Update: The Fenix rcr123a batteries work on both high and low mode with my light. I ran it for 5 mins on high and it didn't shut off. One battery initially wouldn't power the light on high but after about 5 presses it worked on high and has worked ever since.

 

[id30209]

Re: Surefire EDCL1-T Runtime Tests

Update: The Fenix rcr123a batteries work on both high and low mode with my light. I ran it for 5 mins on high and it didn't shut off. One battery initially wouldn't power the light on high but after about 5 presses it worked on high and has worked ever since.

Told ya ;)

 

[Vox Clamatis in Deserto]

Re: Surefire EDCL1-T Runtime Tests

My understanding is the resistor doesn't "signal" the driver to do anything, it just obstructs amperage flow from the battery so the driver can't run at full power.

I get the idea that a resistor in the tailcap is used to signal the controller with the Surefire tactical tailcap from PK's patent 7344270 "Flashlight with incrementing brightness selector switch":

The second path provided by the sleeve allows the switch to connect with the controller over two paths, so that the controller may detect a resistance presented by the switch to determine its state, as will be discussed below. ​

https://patents.google.com/patent/US7344270

Update: The Fenix rcr123a batteries work on both high and low mode with my light. I ran it for 5 mins on high and it didn't shut off. One battery initially wouldn't power the light on high but after about 5 presses it worked on high and has worked ever since.

​

Great news, I'm going to put my Fenix cell back in and see if the multiple presses will make it work properly. The caveat with protected cells is that they can and will suddenly go dark with little warning. In some cases, perhaps a low voltage cutoff, cycling the power will give you a little more light to find those other batteries. In other cases, possibly a thermal high current shutdown, the cell is dead until you put it back on the charger.

 

[fyrstormer]

Re: Surefire EDCL1-T Runtime Tests

I get the idea that a resistor in the tailcap is used to signal the controller with the Surefire tactical tailcap from PK's patent 7344270 "Flashlight with incrementing brightness selector switch":

https://patents.google.com/patent/US7344270

That is an...interesting...choice of wording on Surefire's part. Reading the patent description, it appears that Surefire was trying to patent any switch-and-driver combination that achieves multiple brightness settings by way of operating the power switch. (good thing it didn't work, or almost all the cool flashlights that exist nowadays would've never existed.) But the driver circuit in the EDCL1-T (and in the earlier L1 Lumamax) doesn't "detect" the resistance of the tailswitch in any way that we would describe as intelligent. The driver isn't receiving a signal from the tailswitch like HDS lights do.

There is a single electrical pathway from the negative terminal of the battery, through the switch, through the battery tube, to the negative contact of the driver circuit. That single electrical pathway is, by necessity, the pathway that provides power to the driver. A second electrical pathway would be required for signaling, which is why HDS lights have an extra wire that passes through the wall of the battery tube to make contact with a secondary contact on the driver circuit. Hypothetically the primary electrical pathway could also be used for signaling if the switch were sophisticated enough to create small voltage fluctuations that the driver circuit could interpret while simultaneously receiving enough continuous power to stay operational, but Surefire's switch design is not that advanced. Indeed, a switch design that intricate would almost certainly fail Surefire's "give it to a Marine and see if they can break it" durability tests.

No, the low setting on the EDCL1-T's two-stage switch simply obstructs some of the battery's power, so the driver circuit can't power the LED at full brightness. Based on the article you linked, It's possible the driver has a low-power regulated mode that engages when there isn't sufficient power available to run the high-power regulated mode, rather than just letting the LED run unregulated in the low setting, but that's the upper limit of potential fanciness in this particular design.

 

[Vox Clamatis in Deserto]

Re: Surefire EDCL1-T Runtime Tests

Great news, I'm going to put my Fenix cell back in and see if the multiple presses will make it work properly.

Well, I tried the Fenix cell again, charged it to 4.2 volts, cycled the switch a few times and only got low mode. I let the light run for 30 minutes on low to drop the voltage a little and still just low mode in my case.

I found an old Tenergy LiFePO4 '3.0 Volt' (some Tenergy's are labeled as 3.2 Volt) RCR123A cell and it ran in high for about 20 minutes before noticeably dimming and going dark a few minutes later.

 

[vadimax]

Re: Surefire EDCL1-T Runtime Tests

I use Hixon protected cells in a Backup 300lm and EDCL1-T. Both work perfectly.

 

[coffeeandlifting]

Re: Surefire EDCL1-T Runtime Tests

I found an old Tenergy LiFePO4 '3.0 Volt' (some Tenergy's are labeled as 3.2 Volt) RCR123A cell and it ran in high for about 20 minutes before noticeably dimming and going dark a few minutes later.

LiFePO4 is my favorite cr123 replacement. Its the only chemistry I use in 1x123 lights anymore. Output and regulation are rock-solid due to the extremely flat discharge voltage. Runtime is satisfactory. Just have to carry a spare cell, because that voltage drops like a rock when it's done.

I've gotten good performance out of the K2's, Tenergy, and Soshine (the cheap light blue cells from China).

 

[RobertMM]

Re: Surefire EDCL1-T Runtime Tests

I got two of the K2 energy LiFePO4 cells a couple weeks ago on a whim just because I saw them on a dealer shelf when I was picking up a knife.
I put them in my G2X-LE and they perform great, and i got consistent 0.85Amp readings on high mode which tells me I can expect around 40min on high(consistent with the graphs I've seen from flashlightreviews).

I just didn't think of using them on my EDCL1T as I am trying to burn through a lot of 2021 dated CR123s.

I'll give them a test and get current readings from the EDCL1T as well when I get the time.

 

[270winchester]

Re: Surefire EDCL1-T Runtime Tests

No, the low setting on the EDCL1-T's two-stage switch simply obstructs some of the battery's power, so the driver circuit can't power the LED at full brightness. Based on the article you linked, It's possible the driver has a low-power regulated mode that engages when there isn't sufficient power available to run the high-power regulated mode, rather than just letting the LED run unregulated in the low setting, but that's the upper limit of potential fanciness in this particular design.

That's the way I interpreted it too. On the EDCL-2T I have, the low level is significantly brighter on 2 4.2V RCR123 than 2 primaries, which would not be possible if the low only acts as a signal for the driver to engage "low". I assume EDCL-1T works in a similar fashion but just less noticeable due to its battery voltage parameter.

 

[J_C_S]

Re: Surefire EDCL1-T Runtime Tests

Put a freshly charged fenix rcr123a in my light last night. It took awhile to finally get it to run on both low and high. I pulled it out at work today and it only gave me low so these batteries are a no go for me now. Maybe I need to go unprotected? Has anyone tried an efest unprotected in their light?

 

[fyrstormer]

Re: Surefire EDCL1-T Runtime Tests

All this talk about batteries is thrilling, but I'm going to go off on a mechanical tangent for a minute.

The tailcap on the EDCL1-T is a little narrow for a light that uses a twisty switch. I can appreciate the design consistency of having the same threading and tailcap diameter on the EDCL1-T as on other E-series lights, but it's a little harder to operate one-handed than it ought to be. The clip overlapping the tailcap makes this problem worse. So I went looking for something I could use to make the tailcap easier to twist, especially one-handed, and here's what I came up with:

These O-rings fit super snugly because they're so thick, so they don't shift around at all. It makes the tailcap much easier to grip and turn, especially one-handed, and it also makes it possible to hold the light with a much more relaxed grip without it slipping in my hand. As a bonus, because the O-ring fits so snugly, it also functions as a cigar-ring:

Seated into the groove behind the knurled part of the tailcap, the O-ring sits securely enough that I can press much harder than is actually necessary to operate the switch, and it doesn't even flex, much less move out-of-position. Seriously, it was a huge pain to stretch the O-ring into position -- it will probably never move again.

 

[xevious]

Re: Surefire EDCL1-T Runtime Tests

It's the end of 2018. Frankly, I'm surprised that Surefire hasn't joined in on the ramping game. If this is going to be a 2 mode light, at least let the user program those 2 levels. That way you can satisfy the deep dark user who wants firefly intensity, and the general user that wasn't something bright enough without caring about night vision. And the efficiency maven who doesn't want to be burning hard at 500 max lumens output all the time.

 

[fyrstormer]

Re: Surefire EDCL1-T Runtime Tests

That would run counter to Surefire's military-reliable design philosophy. Soldiers dislike fiddly things, because they have a tendency to not work exactly as expected when you really need them to. That's why half of Surefire's lineup is still single-mode lights.

 

[xevious]

Re: Surefire EDCL1-T Runtime Tests

That would run counter to Surefire's military-reliable design philosophy. Soldiers dislike fiddly things, because they have a tendency to not work exactly as expected when you really need them to. That's why half of Surefire's lineup is still single-mode lights.

I get you. The point being that the "fiddling" would be kept to such a minimum as to be outside the possible "fumble" zone. Like triple click and hold putting it into ramp mode for either M1 or M2 memory positions (whichever one you are on). Once you ramp to the desired output for M1 or M2, double-click sets it. Single click is on-off. Click and hold moves to/from M1 and M2. No strobe, to keep it simple (or hide it with four rapid clicks).

So essentially when the solider is in prep mode at home base, they set the desired intensity for M1 and M2, then don't think about it again. Just use the two intensity modes previously set as needed in the field. Single click-on. Click & hold, 2 secs later mode is changed (M1 <--> M2). Real simple.

 

[RobertMM]

Re: Surefire EDCL1-T Runtime Tests

That is a nice view too, but I imagine the problem is a lot of soldiers who have to mind a lot of other equipment would just want to have two things in mind when using flashlight:
1. Does it work or not?
2. Did I load fresh batteries or not?

Most can't be bothered with rechargeables, and the supply chain keeps em stocked with batteries anyway.