MD63B800

✓ Authorized Siemens distributor

✓ Hard-to-find and manufacturer-specific equipment

✓ Since 1972

Nameplates still read MD63B800 long after the catalog stops listing the part. Nobody has to chase a discontinued number when Bud Ferguson's Industrial Control & Supply Inc. already holds it. Panels in every region of the country get MD63B800 units from a single stocked location. Decades of holding hard-to-find Siemens stock is why a retired designation stays available.

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Benefits Built into the MD63B800 Frame

Eight hundred amps of feeder protection is what an MD63B800 delivers from inside a molded case. Thermal-magnetic tripping handles overload and short-circuit without a separate electronic unit. Interrupting capacity reaches 50 kAIC on a 480-volt system and 25 at 600. Listings to UL 489 and IEC 60947-2 mean the breaker drops into work built to either standard. Compact molded case construction lets the whole assembly fit an ordinary panel cubicle. Tripping happens without a separate control supply, so the unit works unaided.

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Specifications on the MD63B800 Nameplate

Three poles, 800 amps, and 600 volt service define the MD63B800. Designation on the frame is MD, the standard breaking capacity version rather than the high one. Anything in that class comes out of our industrial circuit breakers inventory. Line and load side lugs are type TA3K500 as supplied. Wire range covers 1/0 AWG through 500 KCM in copper or aluminum. Ambient calibration is the standard 40 degrees C rather than a high-temperature variant. Terminations match on either end, since both sides accept the same lug type. Overload and short circuit response comes from fixed thermal and magnetic elements, with nothing to program.

Picking Between Molded Case and Power Frames

Choosing the MD63B800 makes sense for a feeder, while switchgear duty calls for a different class. Main and tie positions in a low-voltage lineup go to Siemens WL breakers instead. The dividing line is the build standard, UL 489 for molded case and 1066 for power frames. Insulated case units fall between those two, and Siemens SBS2020F covers the 2000 frame there. Ampere rating alone will not tell you which of the three a switchboard was designed around. Whichever way that goes, we stock it, down to Siemens SBH2008F at 800 amps in encased gear.

Confirm the Interrupting Rating You Need

Feeder repairs stall when a nameplate reads MD63B800 and no catalog lists it. Pole count, voltage class, and fault rating decide whether a substitute will serve. Cross-referencing is straightforward once our electrical equipment supplier has those three figures. Should no new unit remain, a rebuilt one can be supplied after testing. Delivery leaves one warehouse, wherever the equipment is installed. Ask us to quote the MD6 frame and interrupting rating you need before that panel goes back together.