Rigol DP832 mains earth pin (newbie question!) - Page 1
Forum section: electronics / testgear

author: Xykon
author_rank: Newbie
timestamp: June 09, 2015, 12:25:51 pm
content: Hello,This is probably a very stupid newbie question so please don't laugh too muchI got a Rigol DP832 as my bench power supply and it has an earth ground pin. I was wondering if it's smart to use it to plug my ESD wristband in there or if that could have any negative (or possibly leathal) side effects if something goes wrong in there?I used to plug it into my soldering station which also has a ground pin but then realized the power plug doesn't have an earth pin (one of those flat European two prong plugs) which I understand make it relatively useless.If you agree to the first question, would it make sense to connect the Rigol eath ground to the soldering station and then to the wrist band? To make sure both instruments and myself are connected to earth ground to avoid any ESD issues?I was thinking about getting one ofthese(see picture below) but if the Rigol would do the same thing I could save the money...

author: K1JOS
author_rank: Regular Contributor
timestamp: June 10, 2015, 03:26:09 am
content: You probably would have gotten replies if you posted in beginners section. I believe a basic rule is NOT to daisy chain ground leads because if one fails then all behind fail as well. The best solution for the workbench is to have a single ground bar or plate that is connected directly to the common earth ground back at your electric service panel. If not feasible, at least make sure it goes to a VERIFIED grounded 3 prong outlet and connect your ground bus/plate to it and then use the ground plate as a common ground point for your various pieces of equipment. I always check periodically with a sensitive ohm meter to verify that all my grounds are actually grounded together.JerryK1JOS

author: Xykon
author_rank: Newbie
timestamp: June 18, 2015, 08:45:52 am
content: Thanks a lot for the reply and sorry I couldn't respond any sooner as I've been away on business.My main question was specifically about using the mains earth pin on the front panel of the DP832 (or similar bench power supplies) to plug my wristband, as my understanding is that this pin goes directly to the mains earth of my electric system. My worry is about the isolation on that pin and if there is any chance it could kill me if that power supply has a major malfunction (which is why I decided to post this in here and not the newbie section).I'm now thinking about getting the set pictured below which also comes with a ground plug as pictured above which seems like the most reliable solution. I was planning to get a mat like that anyway...

author: dom0
author_rank: Super Contributor
timestamp: June 18, 2015, 10:11:21 am
content: Simple + cheap solution for ground distribution:Get some blank (no isolators supplied) 4 mm sockets, some copper-clad board, solder them down on the board (that's mechanically rather rigid for our purposes), get some green/yellow PE wire (1.5 mm^2 preferably), get a Schuko / whatever you country uses plug, remove the phase/neutral contacts(!!), fill contact holes with hot-melt. Solder PE wire to board and connect to PE contact on the plug. Bolt board to underside of your work bench / whatever.Board is hard grounded, but that's not an issue since the spiral cables to connect wrists bands all have 1 M? resistors built-in. Also, other stuff on your bench might want a hard ground.Many (all?) ESD mats are made of synthetic rubber and stink like rubber hell for a good while.

author: John Coloccia
author_rank: Super Contributor
timestamp: June 18, 2015, 10:31:08 am
content: Quote from: Xykon on June 18, 2015, 08:45:52 amYes, of course it can, but the same could be said for anything. But that's not why I wouldn't do it. Remember, there's a HUGE resistor in the wrist strap, on the order of 1M, so it's pretty hard to hurt yourself with that thing anyhow. It's just kind of bad form to be grounding yourself to test equipment. Why do you want to hang a big, sloppy antenna off the ground of a precision instrument?Incidentally, at my production bench I ground myself through the ground on my JBC iron all the time. In that case, I only ever use the wrist strap for a couple of operations, all of them involving soldering, so it makes sense to have a short strap right in that area.