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Products => Test Equipment => Topic started by: rauldm on June 30, 2021, 04:09:24 am

Title: keysight U1282A very slow, custom firmware?
Post by: rauldm on June 30, 2021, 04:09:24 am
Hi, I have an U1282A, is good meter but it has a very slow autorange, for example in 40 reads/second mode works fine, but autorange keep seen very slow compared with Fluke 289 or Hioki DT4282, exist some project about custom firmware? can be improve speed with firmware upgrade or is hardware limitation?

Regards.
Title: Re: keysight U1282A very slow, custom firmware?
Post by: coromonadalix on June 30, 2021, 10:54:15 am
You would need to find an firmware update if there is,  or read the mcu(s)  in the meter if they are not read protected,  if you succeed, you would need to disassemble the firmware, reverse engineer it, recompile it and reprogram the mcu ...
Title: Re: Keysight U1282A very slow, custom firmware?
Post by: electr_peter on August 09, 2021, 12:39:29 pm
U1282A is not the fastest in autorange (resistance or voltage/current range), but it is good enough for me. If you need better response, try 40 updates per second mode (limits resolution to 4 digits instead of 5) or enable manual range mode (it is useful in many cases to fix range anyway). It is slow in changing ranges partly because it has got some many ranges in resistance mode.
On the other hand, continuity function on U1282 is very good - fast (does not miss anything), latched and with red LED on top off the LCD.

My little nitpick - when changing ranges in DC voltage mode, "-" (minus) sign is only updated when the range has finally settled. That is, if you try measuring -100 V DC, at first it shows 0.0000 V DC (not yet connected), then LCD digits go blank (minus sign still not illuminated) while range is changing, then final range and value is displayed with correct "-" sign. Point is that polarity can be shown even when range still is changing.

Manual firmware update is not really possible without extraordinary effort. I suggest to contact Keysight directly and ask for autorange improvement. U1282A firmware has been officially updated few times already,  Keysight U1281A/U1282A Firmware Update (https://www.keysight.com/zz/en/lib/software-detail/instrument-firmware-software/u1281au1282a-firmware-update-1765967.html)
Title: Re: keysight U1282A very slow, custom firmware?
Post by: Old Printer on August 09, 2021, 02:01:32 pm
Apologies to the OP for intruding on his post, but I would like to ask a question of electr_peter. I recently bought one of these on the used market. I have not checked what the current firmware version is yet, but assuming it needs updating, should I install them incrementally or just go to the latest release? It is a great meter, but it is slow. I am a hobbyist and this is more meter than I really need, but I came across a deal I could not pass up. Thanks
Title: Re: keysight U1282A very slow, custom firmware?
Post by: electr_peter on August 09, 2021, 02:09:28 pm
... assuming it needs updating, should I install them incrementally or just go to the latest release?
I would install the latest release, risk of bricking is very low. Keysight seems to indicate that installing the latest FW is safe. Also, FW updates are not related to stability or changes in FW update mechanism.
Anyway, I doubt DMM would be perceivably faster after update, but it is your choice.
Title: Re: keysight U1282A very slow, custom firmware?
Post by: Old Printer on August 09, 2021, 02:46:19 pm
... assuming it needs updating, should I install them incrementally or just go to the latest release?
I would install the latest release, risk of bricking is very low. Keysight seems to indicate that installing the latest FW is safe. Also, FW updates are not related to stability or changes in FW update mechanism.
Anyway, I doubt DMM would be perceivably faster after update, but it is your choice.

Thank you Peter. I have a Siglent scope that should be updated and while there have been some reports of trouble, that is still under warranty so I am more relaxed. I assume that since I bought this used that there is no warranty valid, and would hate to brick it.
Title: Re: keysight U1282A very slow, custom firmware?
Post by: rsjsouza on August 09, 2021, 02:52:36 pm
The U1282A indeed has a slow autorange and no firmware update will improve this (I have the latest), but the 4-digit mode surely does - did your used meter come with Keysight's USB isolated cable?

My biggest nitpick with it is the beep volume - only mechanically solved.

Another one is with the button interface - once you get to a specific function (Hz/duty cycle or Peak/Max/Min or Vsense), it is hard to understand how to come back to the original function without rotating the dial.

Otherwise it is a good meter, full of options and absolutely king for datalogging - similar to the U1272A/U1273A.
Title: Re: keysight U1282A very slow, custom firmware?
Post by: Old Printer on August 09, 2021, 05:04:45 pm
The U1282A indeed has a slow autorange and no firmware update will improve this (I have the latest), but the 4-digit mode surely does - did your used meter come with Keysight's USB isolated cable?
No USB with mine, nor the bluetooth adapter. Sounds like the USB cable is something special, can you elaborate please?  Honestly I can't complain, the meter is in like new condition, and was in a box with six sets of Pomona mini grabbers, a few assorted sets of Pomona banana leads and two sets of Keysight probes.
Title: Re: keysight U1282A very slow, custom firmware?
Post by: rsjsouza on August 09, 2021, 07:52:04 pm
The U1282A indeed has a slow autorange and no firmware update will improve this (I have the latest), but the 4-digit mode surely does - did your used meter come with Keysight's USB isolated cable?
No USB with mine, nor the bluetooth adapter. Sounds like the USB cable is something special, can you elaborate please?  Honestly I can't complain, the meter is in like new condition, and was in a box with six sets of Pomona mini grabbers, a few assorted sets of Pomona banana leads and two sets of Keysight probes.
That is indeed quite a nice bundle - congratulations on your purchase!

The cable comes bundled with a new meter - it is isolated and allows exporting the datalog info to a PC and perform firmware updates.
https://www.newark.com/keysight-technologies/u1173b/pc-connectivity-cable-handheld/dp/05X9288 (https://www.newark.com/keysight-technologies/u1173b/pc-connectivity-cable-handheld/dp/05X9288)
Title: Re: keysight U1282A very slow, custom firmware?
Post by: rauldm on August 09, 2021, 08:13:42 pm
I testing with other firmware version from keysight, the autorange is same bad, I testing also with 40 times update but not exist improve in autorange performance, yes, it has good continuity but autorange is incredible slow, I talked with keysight some time ago, they send response with my country representative, his answer was really simple, you must buy other of Keysight  product with more responsive. Also I have the Keysight 34450A and 34401A from HP, keysitht 34450a with last firmware version is also incredible slow.
Title: Re: keysight U1282A very slow, custom firmware?
Post by: Old Printer on August 09, 2021, 09:23:14 pm
rsjsouza, thank you for the link. I had seen that cable but didn't realize it was for firmware updates as well as data logging. I will pick one up, they are pretty reasonably priced. This was a great deal for me, I was looking for a bench meter and stumbled on this on Craigslist. It was too far to drive, so I took a chance when they offered to ship it. It was stupid cheap so worth the risk.
Title: Re: keysight U1282A very slow, custom firmware?
Post by: rsjsouza on August 09, 2021, 10:01:52 pm
rsjsouza, thank you for the link. I had seen that cable but didn't realize it was for firmware updates as well as data logging. I will pick one up, they are pretty reasonably priced. This was a great deal for me, I was looking for a bench meter and stumbled on this on Craigslist. It was too far to drive, so I took a chance when they offered to ship it. It was stupid cheap so worth the risk.
I am glad to have helped.
This is something that puts me off with Fluke - I have an 189 and its IR cable alone is about twice the price on eBay - however, Fluke's official software is not free, which elevates its price enormously.


I testing also with 40 times update but not exist improve in autorange performance, yes, it has good continuity but autorange is incredible slow,
The autorange improves by also selecting 6000 counts mode.

Overall, ohms is the slowest autorange especially when used to measure low resistances, where it navigates across several ranges.

Such characteristics are inherent to the meter's chipset, so firmware can only go so far to improve that.

Title: Re: keysight U1282A very slow, custom firmware?
Post by: rauldm on August 09, 2021, 10:42:17 pm
Today have the fluke 289, 87 IV, u1282a and DT4282, this is the better in speed and stability, u1282a is a good meter but I don't recommend because is not high count like to justify  slow response. I like to much his application because you can use math mode is very useful for work with current clamp and configure correct ratio. Log capability is good but I don't like for is not has time span like Fluke.
Looks like perfect meter because is IP67 rated, backligh in keyboard, waveform generator, very large ranges for resistance, but when you use it, you have a big disappointment  for slow responce.