The rotary actuators are an off-the-shelf item for transfer switches.  No 
problem to get them paired with high-amperage switches. But a contactor, which 
is a solenoid-driven switch, is also an off-the-shelf item. The ones I use in 
EV applications are rated for 1000A, and cost about $300.  You need to be 
careful to look at the trade-off between voltage, amperage, and the per-cycle 
probability of a weld, though.  An over-rated contactor helps a lot if you're 
going to be cycling it a lot, whereas if it's for emergency use only, you can 
hew a lot closer to the max rating. 

    
                -Bill


> On Jan 28, 2015, at 18:40, Robert Drake <rdr...@direcpath.com> wrote:
> 
> For larger DC devices with ~50amps per side, does anyone have a software 
> accessible way to turn off power?
> 
> I've looked into PDU's but the ones I find have a max of 10amps.
> 
> I've considered building something with solenoids or a rotary actuator that 
> would turn the switches on or off, but that's a complete one-off and would 
> need to be done for each device we manage (not to mention it involves janky 
> wiring all over the place I've got to explain to the colo)
> 
> My use case is pretty infrequent so it needs to be remote-hands cheap.. it's 
> for emergencies when you need to completely power cycle a redundantly powered 
> DC device.  The last time I needed this it was because a router was stuck in 
> a boot loop due to a bad IOS upgrade and wouldn't break to rommon since it 
> had been >60 seconds.  It came up again tonight because we wanted to disable 
> one power supply to troubleshoot something.
> 
> FWIW, I believe I've seen newer Cisco gear with high-end power supplies that 
> have a console or ethernet port which would possibly let you shut them down 
> remotely.  That solves the problem nicely if you're dealing with only one bit 
> of hardware, but I'd like a general solution that worked with any vendor.  
> Possibly a fuse panel with solenoids that could add/remove fuses when 
> needed.. or would that be considered dangerous in code-ways or in telco fire 
> regulation ways?
> 
> 
> 
> 

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