ETAP Motor Operated Disconnect Switch (MOD) modeling

[msramek]

Hello everyone,

I am somewhat new to ETAP and specifically more inexperienced in substation design as I worked in water and wastewater for a while doing ArcFlash & Device Coordination Studies via SKM.


I am using ETAP Version 24.0.0 and having trouble figuring out how to model a 1200A, 138kV motor operated disconnect switch that utilizes a 125VDC motor operator.

Initially I just thought to use a high voltage breaker since I can just edit the rating factors, and the interlock logic is already applied to the asset so it can get all the supervisory trips. I also attempted to model it as a regular switch & separate DC motor, and use status & syncs but it seems overly complex considering a motor operated disconnect is basically a breaker that isn't intended to break under load. So I'm curious if anyone has any experience working with MOD switches in ETAP and would like to share how they approach this subject.

Any advice or knowledge is greatly appreciated,

Thank you

 

[D. Castor]

A motor operated disconnect is a switch, not a breaker. You need to determine why you need to even model it. In most cases, I would just model as a manual disconnect and add a note to indicate it has a motor operator. The motor operator isn't going to have any impact on any type of analysis that I can think of.