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  • Duct Smoke Detectors | Information by Electrical Professionals for . . .
    We are receiving feedback that mechanical contractors typically furnish and install the duct smoke detectors and the only responsibility the electrical contractor has is getting the fire alarm wiring to the duct smoke detectors 2 When a fire alarm system is not present, we will typically design a 120 volt circuit to power the duct smoke
  • How far from a Transfer air grill should a smoke detector be?
    Somewhere around 2003 the mechanical code had to come up to date for energy code reasons IIRC Hence, the mechanical contractors started installing a central return air system which saved them from having to duct return air So, a central RA system, yes it is more noisy than a fully ducted system, becomes the norm
  • TC or Tray Cable | Information by Electrical Professionals for . . .
    (7) In industrial establishments where the conditions of maintenance and supervision ensure that only qualified persons service the installation, and where the cable is continuously supported and protected against physical damage using mechanical protection, such as struts, angles, or channels, Type TC tray cable that complies with the crush
  • Arc Flash PPE for HVAC work lt;= 480V | Information by Electrical . . .
    Will be doing NFPA 70E training with a mechanical service contractor who has HVAC technicians working on equipment typically operating at 480V and less As you can expect, most of the commercial locations where they do service do not have Arc Flash Labels on their equipment Per NFPA 70E, if
  • Another large contractor closes its doors
    Back in the late 90's there was a company out of Texas called Consolidation Capital Corporation Encompass Mechanical Services that went on a buying spree They bought up large electrical and mechanical contracting companies in the Denver, CO area
  • Demo- Safe-Off Disconnect | Information by Electrical Professionals . . .
    Call the GC or spell it out in your proposal We typically do a 'make safe only' which amounts to disconnecting all the circuits at the source in a way that is safe and could be left indefinitely than the GC brings in demo contractors that strip out all the feild wiring
  • ELECTRICALLY HELD VS. MECHANICALLY HELD CONTACTOR
    In a super quite area like a broom closet in a library you might hear the coil "hum" from a electrically held device so a mechanical one would be preffered In a basement boiler room who care about noise Life of the coil is not really a concern for most vendors
  • Subcontracted Electricians working under the Contracted Electrician in . . .
    North Carolina has made this illegal for a while now The state's stance is the EC can 1099 someone that has a NC contractors license, or pay a W2 employee The EC may not pay a 1099 employee to do electrical work if that employee does not have a contractor's license (in NC there is only a contractor's license, no Journeyman or Master's certs)
  • Motor starter or just a disconnect? | Information by Electrical . . .
    They are also typically limited to small motor controls where the overload disconnect action can be accomplished using springs and such Above about 50HP, the mechanical forces necessary to keep the contacts from forcing each other apart under normal load make mechanical motor starters difficult to make and use
  • Receptacles at Tree Grate - Electrical Contractors Help Requested
    Electro-Mechanical Technician Industrial machinery Jan 19, 2012 #16





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