[169853] in North American Network Operators' Group

home help back first fref pref prev next nref lref last post

Re: L6-20P -> L6-30R

daemon@ATHENA.MIT.EDU (Jeremy Bresley)
Tue Mar 18 22:34:31 2014

Date: Tue, 18 Mar 2014 21:34:24 -0500
From: Jeremy Bresley <brez@brezworks.com>
To: nanog@nanog.org
In-Reply-To: <6818639.12069.1395184316156.JavaMail.root@benjamin.baylink.com>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org

On 3/18/2014 6:11 PM, Jay Ashworth wrote:
> From: "Randy" <amps@djlab.com>
>> I have a situation where a 208v/20A PDU (L6-20P) is supposedly hooked to
>> a 208v/30A circuit (L6-30R). Before I order the correct PDU's and whip
>> cords...sanity check...are connectors 'similar' enough that this is
>> possible (with force) or am I going to find we've actually got
>> L6-20R's on the provider side?
> As it happens, the chart at
>
>    http://www.stayonline.com/reference-nema-locking.aspx
>
> suggests that the L6-20 and L6-30 are less different than you'd expect.
>
> I *think* those are on different diameters, and a datacenter employee ought
> to friggin' know better... but I don't think it's 100% impossible that this
> has happened.
>
> If it did, you're gonna replace the plug anyway...
>
> As long as there's a 20A breaker on the PDU, you're safe, if not within
> code.
 From experience with some electricians who couldn't follow simple 
written instructions, it is physically possible to put an L6-20 plug 
into an L6-30 receptacle.  But it won't lock into place.  Beyond all the 
other reasons it's not recommended, the slightest bump of the cable will 
likely knock it loose causing whatever is on there to drop.  (Cue 
electricans knocking the production 6506E's offline 3 times in 20 
minutes while they were replacing the breakers and the supposedly 
redundant power cords...)

If you can unplug it to look, every one I've ever seen has had the 
voltage and amperage clearly molded into the face of it.

Jeremy "TheBrez" Bresley
brez@brezworks.com


home help back first fref pref prev next nref lref last post