IET DE-6000 LCR meter churns power: is it just my unit or it's by design?!? - Page 1
Forum section: electronics / testgear

author: k4rlhp
author_rank: Unknown
timestamp: July 17, 2015, 09:25:26 am
content: Hi.Of all the discussion around the DE-5000&DE-6000 LCR meters, I could not find anyone mentioning power consumption...Bought myself the IET DE-6000 and after three days+some hours over on standby (i.e. the OFF state) I got surprised by an empty battery.I only did some initial verification after receiving the unit by running it on a couple of caps and resistors and inductors (maybe 10 tests total) with battery indicator on full after I finished.The unit is brand new and the battery was brand new duracell nicely packaged and well within it's shelf-life period.Imagine my surprise when returning to the unit after under 4 days of receiving the unit and getting message "batt" and nothing else?I ran a number of tests and it turns out like this.ON+idle state power consumption ~100mWON+active test (100kHz test on an inductor, the highest power consumption level I achieved) ~260mW. Maybe it goes higher with sometihng but that's not so important.This gives around 30 hours battery life when ON and in test, which is no shock considering LCR meters but clearly that transformer in the kit is included for a reason.OFF mode13mW@9V3mW@6,7V (close to dropout)Average is 7mW which exhausts the supplied battery in ca. 70h... (based on DuraCell 9V 6LR61 MN1604 battery data sheet)This is unacceptable.You just cannot keep the battery in the unit!?!I know there are other people on this forum who have either DE-5000 or DE-6000 at their disposal.A question, is this issue inherent to the design (verified by other users) or is it just my unit and I should return it across the globe to IET?I'll define the issue for clarity sake: OFF condition dries off the battery in 3..4 days.Or should I just go look in the mirror?Br,

author: cs.dk
author_rank: Unknown
timestamp: July 17, 2015, 09:33:40 am
content: I haven't measured powerconsumption (can do that later). But my DE-5000 has not been used for probably 2-3 months, and it still powers up with no low battery warning.IIRC i've changed the battery 2 times, in ~2 years i've had the unit.Sounds like a fault to me. What does IET support say?

author: kripton2035
author_rank: Super Contributor
timestamp: July 17, 2015, 09:50:01 am
content: same here, never changed the battery of my deree de5000 since october 2014...

author: Fraser
author_rank: Super Contributor
timestamp: July 17, 2015, 10:25:30 am
content: My DE-5000 has been sat on the shelf for 4 months unused and the battery is still fine.It sounds like you have a faulty unit as such high battery consumption would normally cause a stir amongst users that could easily be found with Google.I had a faulty new piece of equipment that suffered a similar issue. It turned out that in the 'off' mode an amplifier chip was still being powered. A supply control MOSFET dedicated to the chips power rail was S/C S to D. I found the fault using a thermal camera as it was easy to see the chip glowing, even when the unit was in the 'off' mode. OTT I know but it was so easy to doAurora

author: radioFlash
author_rank: Regular Contributor
timestamp: July 18, 2015, 01:49:09 am
content: I get 1.74 µA in standby and about 15.5 mA when turned on.

author: k4rlhp
author_rank: Unknown
timestamp: August 27, 2015, 07:24:11 am
content: Thanks for input.I contacted IET and they were very kind to send me a new unit after asking me to confirm the measurements.IET informed me that they know the issue and are now checking all units prior to shipping.I also got to keep the old unit that chews batteries. That one I can use by attaching to a power cord.The new DE-6000 unit measures 2.6uA at 9V on standby, and around 9mA in ON mode/idle.So now I can use batteries which is far more convenient. Somehow one is always short of power outlets in lab.IET service was very professional. Thumbs up.Regards!K

author: TheBay
author_rank: Unknown
timestamp: August 27, 2015, 09:25:30 am
content: That's a really good outcome! Top marks to the manufacturer.Are you liking your DE-6000?Quote from: k4rlhp on August 27, 2015, 07:24:11 am

author: k4rlhp
author_rank: Unknown
timestamp: August 27, 2015, 01:57:25 pm
content: Quote from: TheBay on August 27, 2015, 09:25:30 amYes SirThere are some things that specifically bother me but otherwise the unit is a strong performer at what it does and it's mostly better than competition.One-up would likely be a bench instrument at several times the cost, which I will consider as-late-as-possible.Since purchase it's one of those instruments that seems to be often used rather than one that mostly sits on shelf.I guess that's the ultimate test.K

author: Muxr
author_rank: Super Contributor
timestamp: August 27, 2015, 02:48:11 pm
content: I have the DE-5000, for the life of me I don't understand why they went with a soft power off. It's a device most of use maybe once every few months. The battery seems to last for awhile though.

author: k4rlhp
author_rank: Unknown
timestamp: August 28, 2015, 02:13:14 pm
content: Quote from: Muxr on August 27, 2015, 02:48:11 pmThe user manual does not appear to mention when one needs to perform the calib. routine.Perhaps it will lose calibration values when you remove the battery?Just a wild guess, I haven't actually checked on this.And when the best accuracy is important, one will certainly calibrate prior to measurements.Anyway, ~20uW sby is acceptable, battery will last a while and will rather die out of usage than sby.After all, the power drain difference is 3 orders of magnitude between sby and on.K.

author: Macbeth
author_rank: Super Contributor
timestamp: August 28, 2015, 02:42:57 pm
content: Sounds like that will be an easy fix. In fact you might find the fault is blindingly obvious, likely caused when IET hamfistedly peeled off the old DE-5000 faceplate to put the shiny new DE-6000 faceplate over it.Maybe during the "custom firmware" upgrade (flashing the 256 byte 24C02) they snagged a battery lead and left it exposed shorting out something?I think a teardown and repair is in order.

author: wraper
author_rank: Unknown
timestamp: August 28, 2015, 02:55:34 pm
content: Quote from: Muxr on August 27, 2015, 02:48:11 pmWhy not, self discharge of the battery is higher than device consumes while being off. There is no real reason to add additional switch which will increase cost and likely add additional failure point.