Side note for you young guys. Was a commercial sparky for 50 enjoyable years and ALWAYS had the most trouble with POS GE! We had over 50 MCC locations supplied by 4 different companies. Piece of garbage GE'S always ran 25 to 30 degrees F hotter. Had trouble with every medium voltage dual service POS GE expensive switchgear. GE was the worst company for tech support & trying no begging to get replacement parts. Took their crack service department a year to get a replacement under voltage relay for 8 year old 13,200 volt switchgear the another year to get a wire schematic for he morons to figure out where 5 wires go. Da two to coil, one to common side , one to NO & one to NC contact.
While you can buy empty buckets generally whoever manufactures the MCC offers premade buckets that simply slide in. Parts will always be a disconnect, motor starter and fuses. But more can be added from there based on what the individual bucket will be powering. For example in our facility all of our exhaust fan MCC buckets have line voltage into a fused disconnect, contactor, thermal overload relay, fused output legs to the fan motor, time delay relay (so we can stagger the fans to not start simultaneously) , and a step down transformer from 480V to 120V (control voltage to energize the coil of the contactor) In our case it’s way overkill for simply starting restroom exhaust fans but our company has no budget whatsoever. They’re also interlocked to the AHU’s so the exhaust fan sends a 120V proof signal to a MBC panel which checks the PXCM panel at the pressure switch to verify the AHU is running. Once the AHU proofs it sends a 24v signal from the PXCM to MBC panel, closes a 24V relay, allows the 120 sent out from the MCC bucket to return and complete the circuit thus starting the time delay relay, starting our exhaust fans.
1:04 mark - MCCs are just one of the switchgear types involved in arc flash/shock accidents (mainly due to the higher voltages used), so being absolutely sure the stuff is powered down/de-energized before doing any work inside MCCs are definitely key here.
Awesome video! Hope to see you release the vfd video soon. I’m a senior studying chemical engineering but am working with the I&E team rn. So this video came in clutch! Thanks for the content and knowledge
Awesome video.. I am searching for a video on how and what I could control with the contractor DPC-30A3P120 but can't find one. hope anyone could help me .
@worldofInsightfulthings excellent, can't wait to check it out tonight! This MCC vid gave me so much insight on some basic concepts I needed for the BAS at work, and now I actually manage the legacy system integrations for our BAS, so once again, greatly appreciate it!
