Using a 30Amp circuit instead of a 20Amp circuit for Catalyst 6509 E with 6000W power supply

[wingchingleung]

So far I have been following the guidelines from Cisco on power provisioning for my racks in which my older 6509E switches reside :

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst6500/hardware/Chassis_Installation/Cat6500/6500_ins/0apwsply.html#wp1026788

Here is the power supply and connector information

• Power supply model: WS-CAC-6000W (5771.64 Watts = 137.42 amps @42V)
• Power supply mode: Redundant
• Power connector type: CAB-AC-2500W-US1= (non locking 250VAC 16A) 

As I have been trying to consolidate the equipment to using less rack space I find myself in a position to have other network equipment occcuping the same rack space as the 6509E and I was wondering if i can change the circuit from 20Amp to 30Amp for the rack so that I can mount other network equipment and plug into the same power strips to the dedicated circuit which the 6509E are connected to (used to be 20m for A and 20m for B - one for each power supply). Please advise if this is a bad idea to change the circuit Amp to accomodate additional equipment moving to the same rack.

[whiteside998]

hi wingchingleung

suppose this would really depend on the setup of the space.

you may have to consider, 

- UPS capacity if you have multiple units protecting different circuits / racks already

- how much risk is being added, with the equipment being consolidated into the one rack on a single circuit 

- distribution boards have the capacity for the additional requirements

- if there a heat issues by moving equipment around the room if this is an issue

- and total power consumption of all equipment once installed

i know you most likely have already considered all of this but thought i would through my two cents in

but hopefully this helps out a little.

[wingchingleung]

Thanks for the response. Yet let's say if I keep the rack as is - meaning only having just one C6509E switch are there any disadvantanges from switching  the circuit from a 20Amp to a 30Amp ?  One of my goal is to standardize on the power to the Racks in the data center (to using all 208V 30A). Thanks.

[whiteside998]

Hi wingchingleung

i am not to familiar with the exact power requirements of the C6509E as it can vary dependent on configuration

Cisco do have a power calculator that may or may not help haven't had a chance to play with it but can be found here

http://tools.cisco.com/cpc/

but the main disadvantage to this would be cost at the end of the day upgrading the power from 20 amp to 30 can be expensive depending on the amount of work required

but you mention 208 ? or is it 240 ?

but as far as power is concerned seems like it would be fine by the ruff rule of V x A = W

so 240 * 30 = a max of 7200w draw

so sorry i cant give you a the straight answer but maybe some may be able to answer more directly.

but let me know if i helped at all

thanks again

[cbaranoski]

Hi wingchingleung,

Aside from whiteside998's points, you're going to have to some changes to your electrical wiring.  You power supplies are likely using NEMA 6-20P plugs (you mentioned non-locking 250VAC, 16A).  To get 30A circuits at 250V, you'll need to replace your receptacles with NEMA L6-30R receptacles.  So you'll need your new power strips, as they will have the wrong connectors.  You should be able to get new power strips that will have 6-20R receptacles for your switches and an L6-30P plug to go to your new 30A receptacle.

You'll probably also need to get the wiring between the breaker and the receptacle replaced with some bigger gauge wire too...