Differences between Maynuo M97 and M98 LED DC Loads? - Page 1
Forum section: electronics / testgear

author: echomancer
author_rank: Contributor
timestamp: December 02, 2013, 04:11:06 pm
content: Good morning folks.I'm struggling to understand the differences between these two units. Does the M98 do everything that the M97 does and then some?I've not found much clarity on the "LED Driver" function. It specifically says "LED mode for LED power driver test, steaday reading, compatable with simulating the capacitances sensitive driver".Apologies, as this seems like it should be a simple question to answer, but I'm still learning. I use DC Loads to test batteries, power supplies, and solar charge controllers, so that would continue to be my intended use and I want to make sure that I don't pay for something I will never need. On the other hand, I don't want to miss out on something that I might need in the future while I'm looking to buy one of these machines.Thanks in advance for the input.

author: echomancer
author_rank: Contributor
timestamp: December 03, 2013, 07:12:37 pm
content: No one at all?I would even take someone who owned the 98 just telling me how they use that feature!

author: linux-works
author_rank: Super Contributor
timestamp: December 23, 2013, 04:47:49 pm
content: I'd also like to know this answer.my GUESS (just to stimulate a reply, if I'm wrong) is that the display is LED (or lcd) instead of fluorescent.if this is correct, some obvious pros/cons: vfd is brighter and reacts faster than lcd (numbers would update faster). vfd will have a higher voltage driver inside (dc/dc) and that could 'sing' over time. lcd backlights are low power and don't sing. lcd does not burn out over time but vfd will (if you leave it on for long periods of time, the vfd does burn in). replacing a standard hitachi style lcd is possible later on; but custom vfd's may not be easy to find later.again, I'm not 100% sure its just the display, but from reading the ads, this is the best I can glean. I'll ask a seller, as well, and see what they say. I still prefer vfd for test gear and I'd pay extra for the vfd instead of paying extra for the lcd, but that's just my personal pref.

author: eurofox
author_rank: Unknown
timestamp: December 23, 2013, 04:51:46 pm
content: Hi,I have a Vantek and it work like expected but the Windows software is crap.In my case I only need the hardware and don't need the Windows software supplied.eurofox

author: Rufus
author_rank: Super Contributor
timestamp: December 23, 2013, 05:07:05 pm
content: Quote from: echomancer on December 02, 2013, 04:11:06 pmLike most things cheap and Chinese clarity is hard to come by.My guess is it is just an LED simulation mode which would be constant voltage plus some series resistance. Probably just a variation of software algorithm to control the same hardware.Realistic LED simulators would have to behave well when the driver uses PWM dimming. I doubt they did anything special in hardware to support that.

author: dadler
author_rank: Unknown
timestamp: March 25, 2015, 09:32:35 pm
content: Sorry to bump a really old thread, but I could not find the answer to this question anywhere. Is the hardware actually different between the M97XX and M98XX series, or is this just a firmare feature?

author: saturation
author_rank: Super Contributor
timestamp: April 01, 2015, 03:22:03 pm
content: IIRC the main difference is the programmed LED driver eload test in the M98xx series, which has some slight differences over a standard eload test, the key being a softstart to prevent current spike related damage to the LED drivers. I don't know if it has hardware differences. This is of concern with high power LEDs.Quote from: dadler on March 25, 2015, 09:32:35 pm

author: georges80
author_rank: Frequent Contributor
timestamp: April 01, 2015, 03:39:13 pm
content: I have an M9812 and I work/design LED drivers.I have found that the LED 'mode' (you select it via the front panel - key sequence, no dedicated switch) is mostly useless since it causes stability problems (hunting) with many boost drivers. So, I just use it in the non-LED 'mode' (constant voltage load) and it works well. Worst case I add some parallel capacitance to stabilise some drivers.No idea if it involves any hardware difference or whether it is just a firmware difference. Anyhow, I would not specifically purchase the M9812 for the LED load 'feature'.cheers,george.

author: jadew
author_rank: Frequent Contributor
timestamp: April 01, 2015, 07:30:21 pm
content: I remember reading that the 98 series was made for export (better caps, higher quality components) while the 97 series was made for the internal market (cheaper).

author: wraper
author_rank: Unknown
timestamp: April 01, 2015, 07:31:58 pm
content: Quote from: jadew on April 01, 2015, 07:30:21 pmActually M98 are much cheaper.

author: jadew
author_rank: Frequent Contributor
timestamp: April 06, 2015, 01:03:46 pm
content: Quote from: wraper on April 01, 2015, 07:31:58 pmWhere?

author: wraper
author_rank: Unknown
timestamp: April 06, 2015, 02:46:10 pm
content: Quote from: jadew on April 06, 2015, 01:03:46 pmHmm, they were about 2 years ago when I bought my M9712. After I ordered it on ebay from China, noticed that I could get M9812 on aliexperess for about 30% less (M9712 on aliexpress cost about the same as on ebay). I then wondered because the specs seemed to be the same except LED (advantage of M98). Now I checked again, prices of both are about the same, M9712 being about 5-10% cheaper. I see that M9712 significantly dropped in price but M9812 rised. IIRC at that time M9812 could be ordered for about $360-$400 + shipping while M9712 was about $600+shipping.

author: Howardlong
author_rank: Super Contributor
timestamp: April 06, 2015, 02:53:48 pm
content: I also noticed the price discrepancy, and assumed the LED version wouldn't have all the functionality of the non-LED version (I don't know that, I just didn't want to take the risk), so I bought the M9712 as I didn't have any particular application for the LED functionality anyway.