Mailing List Archive

On Mon, 10 Nov 2003, Scotty wrote:

> What sort of power do I need to handle a dual-ps M160. If I read the manual
> right it says 65Amp -48V to -60V DC power. Do i really need 65 amps? will
> a pair of 20amp circuits be enough if it is the only thing connected.

Unlikely that you will need the full rated current, but you'd best be
checking it with the JTAC. IIRC, it has to do with how many FPC and PIC's
you have installed. Interestingly enough, the juniper site doesn't list
max current on the M-160:

http://www.juniper.net/products/ip_infrastructure/m_series/100042.html#04

For our M-40's it lists 13A at 240VAC as the maximum it will draw. In our
test lab we actually measured it at 1.6A (at startup, running current was
more like 1.1A) distributed between the PSUs, but that's with only a
handful of PICs plus a routing engine.

IIRC, the JTAC has info on current pull for the individual components so
you can total it up.

HTH,

Rich

On Mon, Nov 10, 2003 at 03:58:26PM -0500, Scotty wrote:
> Hi Guys,
>
> What sort of power do I need to handle a dual-ps M160. If I read the manual
> right it says 65Amp -48V to -60V DC power. Do i really need 65 amps? will
> a pair of 20amp circuits be enough if it is the only thing connected.

http://www.juniper.net/techpubs/hardware/m160/m160-hwguide/m160-hwguide-site-power-reqs.html

Unless you really have that fella maxed out, you're not going to be
anywhere near 65A, though 20A is a bit on the low side. Dual power
supplies share the load equally when both are operational.

--
Richard A Steenbergen <ras@e-gerbil.net> http://www.e-gerbil.net/ras
GPG Key ID: 0xF8B12CBC (7535 7F59 8204 ED1F CC1C 53AF 4C41 5ECA F8B1 2CBC)