Tuesday, June 22, 2010

Sayonara to Sanwa DMMs

It may be strange to hear but the only multimeters I've used over the decades are those by the Japanese company Sanwa.I've laid hands on various Made in China meters, some of which were Fluke look-alikes, but hey those meters aren't even worth having had for free.

In my small collection I have a very old N101 (purchased c.1970s) which I inherited from my dad. I'm still using the original test leads, and have the original box and its manual (which includes a complete schematic). I really like this meter, specially its exterior design. I don't think there's a Sanwa analog meter that can beat its clean, smart, modern, look. I've burned this meter in the past--accidentally poking the VAC mains while the range switch was set to ohms. You get the shock of your life from the BZZZZT that goes off inside the meter. And you end up with deep fried resistors for lunch. Great thing about these old analogs is that they use large through-hole components which are so easy to replace. Take out the burnt component and solder in a new one and it's good to go again. No ICs to worry about. No surface mounts. Of course, accuracy isn't one of its strong points. But it's good to have one (inexpensive) analog around, even if only as a backup meter. And hey, this N101 is quickly becoming an antique. Maybe it's already appreciating in value. This unit is a keeper. I want to pass it on to one of my nephews--one who will eventually grow up to have a love for electronics/electrical work.

About two decades ago I bought my first digital multimeter--the CD721. (Sorry no pics available.) As always I wrecked this meter within a couple of years. Shot its brain with 240VAC while it wasn't expecting it--ohms range. And moreover, the plastic casing is now bloated. I can't remember exactly how that happened, but it could've been because I left it baking inside the car while it was parked in the sun--we're talking of something like 50Celsius. The CD721 is with my sister now. I have no use for that piece of junk. Her kids like playing around with it though. Yes, I have taken precautions so that the little ones won't be able to stab themselves with the probes or get themselves roasted poking into outlets.

Got a CD771 back in 2007 for around $65 to $70 (depending on what the dollar conversion rate was at that time). I don't even use my meters on a weekly basis. And yet this dang unit has already been on the blink for a year now. It just sucks. When this meter works, it works quite well. But when it's in a fit, it'll throw garbage at you. During those moments, the meter might give yo a reading of 40V while you're measuring a 5VDC circuit or it might even display "OL" meaning it's out of range. And the resistance might read several megohms when you short the probes and autoranging slows down to a crawl. To get the meter to work again I switch it off then on again. Usually after one or two such resets the meter gets its sanity back.

So in terms of ruggedness and reliability I can't but give Sanwa digital multimeters a two thumbs down. I've really become sick and tired of Sanwa DMMs that I got myself a Fluke. No cheapo. The Fluke 80 series is some 5 times pricier than the Sanwa. It hasn't arrived but I know I won't be disappointed. And that's one DMM I'm certain will proudly be on my bench and in my tool box for decades to come.

2 comments:

  1. Hello,
    I burned my sanwa too.
    could you give me some resistance ratings in order to get mine replaced correctly ?
    thank you! :D

    ReplyDelete
  2. A digital multimeter is a versatile tool that integrates three testing devices - a voltmeter, ammeter, and ohmmeter - into one easy-to-use handheld unit. The Multimeter Guide

    ReplyDelete