I'm working on a project that includes a 125A main breaker feeding a Siemens imaging piece of equipment albeit via two paths; 1) via a UPS and one a direct connection to the Equipment branch of the hospital. Siemens requires an EPO to shunt trip the breaker and to connect into the EPO point on the UPS (which happens to be a PowerWare (Eaton) 9390, 40kVA. Not sure what to provide for control power. Will check with PowerWare rep. But does anyone have any experience with these?
Thanks,
Mike
When you mention a shunt trip the first thing that comes to my mind is a device the trips the breaker when 120vac is applied to it. In order for the breaker to be closed again power most be remove from the ST on order for the breaker to be manually reset/latched and closed. STs are available in an assortment of other voltages depending upon the power sdoiurse that you have available.
120vac is a commonly available voltage which could be sourced from a regular lighting circuit. It also could be supplied through a CPT with any number a secondary voltages and s matching ST.
A basic contact closure in series with the power sorvce and the ST in all that is required to active the ST and trip the breaker. The contact is not required to be momentary as the is a integral cutoff switch with the ST coil that opens automatically.
It must be pointed out that there must be as reliable power source.
If it is required to trip a breaker w/o a power source a device called a capacitive trip device with a match ST could be used to open a breaker.
The are also flux transfer shunt trips which are able trip with very little current when paired with a proper device that activates the ST.
