Cut Sheet

www.tnb.ca
B49
Industrial Fittings
T&B
®
Fittings
Rigid and Intermediate Metal Conduit Fittings
Methods of Bonding and Grounding (cont’d)
Grounding Clamp
Load side
of service
e
quipment
Bonding Service Equipment
(CEC Rule 10-604)
Bonding jumper required
by CEC Rule 10-606
CEC Rule 10-806
B
onding required by CEC Rule 10-606
Bonding Method per CEC Rule 10-806
Grounding Electrode Conductor
Service conduit
(Threaded rigid metal
conduit or intermediate
metal conduit)
Neutral Bus
Ground Bus
1
Service equipment enclosure
Bonding required by CEC Rule 10-604
Bonding Method per CEC Rule 10-806
2
1
Grounding Electrode
Conductor Enclosure
Grounding
Electrode
Service Conduits
Bus Bar
Service
enclosure
A B C D
Ground Bus
2
Multiple Bonding of Service Raceways Where
Service Entrance Conductors are Paralleled in
Two or More Raceways, CEC Rule 10-614
Rigid metal conduit or
Intermediate Metal Conduit
2
Install Bonding Jumper to Assure Electrical Continuity Between
Isolated Sections of Raceways (CEC Rule 10-614)
Threaded rigid metal conduit
or intermediate metal conduit
1
1
2
Threaded rigid
metal conduit or
i
ntermediate metal
conduit
1
Equipment
bonding
jumper
(i) Installing bonding jumper around unpunched concentric or
eccentric knockouts in sheet metal box or enclosure
[CEC Rule 10-806]
(ii) Installing bonding jumper in hazardous locations where
‘locknut bushing’ or ‘double locknut’ type of contact is
unacceptable method for bonding purposes [CEC Rule
18-074]
1
T&B Series 142 Locknut
2 T&B Series 3870 Bonding and Grounding Bushing (Threaded)
3 T&B Series 5262 Sealing “O” Ring
4 T&B Typical Bolted or Pressure Lug
Suggested Specifications
Insulated grounding and bonding bushing (Series 3870)
Where code requires bonding and grounding of single or multiple metal conduits,
or positive bonding and grounding of metal conduit to the box, enclosure or
auxiliary gutter, the end of the conduit shall be equipped with an insulated
metallic grounding and bonding bushing such as Series 3870 manufactured
by Thomas & Betts.
Grounding and bonding bushings used shall be approved for the purpose and
(1) Shall be of malleable iron/steel/aluminum construction
adequately protected against corrosion
(2) Bushing insulator shall be listed or certified for 150°C/302°F
application with a flammability rating of 94V-O. Insulator
must be positively locked in place
Threaded Rigid Metal Conduit
or Intermediate Metal Conduit
5
4
1
2