BM786 vs new BM2257 - Page 1
Forum section: electronics / testgear

author: abiss221
author_rank: Newbie
timestamp: March 26, 2025, 09:19:48 pm
content: I am having a hard time deciding between these two. I don't do anything serious enough to probably warrant either of these - occasional Arduino projects, DC motors, a decent amount of electrical work on my van (nothing too involved though - chasing shorts etc).It seems the newer 2257 has a couple features over the 786 - serial interface, orange backlight, smaller, latch vs probeThe 786 has a 1000V CatIII rating - although I don't do much with mains currently but may in the future, also some better specs over 2257 like bargraph speed (less segments though), but nothing huge.Does anyone know off top of their head what the 786 can do that the 2257 can't aside from the higher CatIII rating? Or vice versa?

author: J-R
author_rank: Super Contributor
timestamp: March 26, 2025, 11:41:02 pm
content: Quick note, avoid double-posting.These forums have a lot of good info, but also check out Youtube for reviews of DMMs you're interested in. They are a good way to absorb some information. Don't watch every minute, just skip through to see each feature being demonstrated.What DMMs do you have currently? For working on the van, just get a cheap $20 DMM from your local hardware store?Short answer is that while they might be somewhat similar with regard to features, the number one differentiator between the two is the number of counts/digits on the display and the associated accuracy & precision. For the tasks you've mentioned, I don't see that being a requirement, so the BM2257 is probably the way to go since it has Auto V/LoZ while the BM786 doesn't. Or just buy the BM789 from Welectron, which is probably my recommendation for electronics, although the BM869s is another good option (doesn't have LoZ either, but does have a dual display).

author: mwb1100
author_rank: Frequent Contributor
timestamp: March 27, 2025, 02:51:28 am
content: Quote from: abiss221 on March 26, 2025, 09:19:48 pmDifferences mentioned in the datasheets:Code:BM2257 BM786 comments-------- ---------- -----------------------------------------------Basic DC accuracy: 0.4% + 3 0.05% + 5 keep in mind: 1 digit on the 786 is equivalent to 10 on the 2257PC Connectivity: yes no requires purchase of an optional cableAutocheck/LoZ: yes noBandwidth: 500 Hz 7 kHzLogic level freq: 200 kHz 1 MHz BM2257 took a step back from the BM257s which has 1 MHz logic freqIntelligent APO: yes noThe BM786 comes with a nice set of silicone probes instead of the standard PVC probes. The BM2257 also comes with those silicone probesif you buy from the EEVBlog store(I'm not sure about the probes from other vendors)There is also the obvious size/weight difference and the CAT rating that you mentioned.

author: Fungus
author_rank: Super Contributor
timestamp: March 27, 2025, 04:24:27 am
content: Quote from: abiss221 on March 26, 2025, 09:19:48 pmCorrect, and I'd personally go for something simpler.Less button presses, less clutter on the display, less hassle to use.(less LCD segments on the display usually means better contrast, too)There's practical considerations, too, eg. Brymen's "industrial" meters have recessed screens so they don't get scratched so easily when you're in the garage.