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The NEMA enclosure performance ratings for each of our heads are listed to help you select the proper head for your application. The most
common NEMA Ratings for thermocouple connection heads in our catalog are the NEMA Type 2, 4, and Type 4X. Their definitions from the Na-
tional Electrical Manufacturers Association Classification detailed in
NEMA 250-1997
are shown below.
√
NEMA 2:
For indoor use to provide personnel protection against incidental contact with the enclosed equipment and provide protection
against from falling dirt, dripping, or light splashing water.
√
NEMA 4:
For indoor or outdoor use to provide protection from falling dirt, rain, sleet, snow, windblown dust, splashing water, hose
directed water, and will be undamaged by the formation of ice on the external surface of the head.
√
NEMA 4X:
For indoor or outdoor use to provide protection from falling dirt, rain, sleet, snow, windblown dust, splashing water, hose
directed water,
corrosion
, and will be undamaged by the formation of ice on the external surface of the head.
SH - Standard Head - Screw Cap & Chain - Aluminum
Part
Process
Conduit
Block
Elements
Dimensions
Number
Thread
Thread Included
Wires
NEMA Rating
Figure
SHS02
SHS08
SHS12
SHD02
SHD08
SHD12
SHT02
SHT08
SHT12
SHTR02
SHTR08
SHTR12
NPT
1/8”
1/2”
3/4”
1/8”
1/2”
3/4”
1/8”
1/2”
3/4”
1/8”
1/2”
3/4”
NPT
3/4”
3/4”
3/4”
3/4”
3/4”
3/4”
3/4”
3/4”
3/4”
3/4”
3/4”
3/4”
AWTS
AWTS
AWTS
AWTD
AWTD
AWTD
AWTT
AWTT
AWTT
AWTR
AWTR
AWTR
Single / 2
Single / 2
Single / 2
Double / 4
Double / 4
Double / 4
Triple / 6
Triple / 6
Triple / 6
RTD / 6
RTD / 6
RTD / 6
Height
3.6” or 91.4 mm
Width
3.6” or 91.4 mm
Cap Diameter
3.1” or 78.7 mm
NEMA Rating -
Type 4
For 1” NPT Process Threads use the following AWH Heads:
AWHS16, AWHD16, AWHT16 AND AWHTR16
Use Connector Blocks: AWTS, AWTD, AWTT and AWTR, respectively.
SH
1
AFTH - Aluminum Flip-Top Head
Part
Process
Conduit
Block
Elements
Dimensions
Number
Thread
Thread Included
Wires
Figure
NEMA Rating
AFTHS02
AFTHS08
AFTHS12
AFTHD02
AFTHD08
AFTHD12
AFTHT02
AFTHT08
AFTHT12
AFTHTR02
AFTHTR08
AFTHTR12
NPT
1/8”
1/2”
3/4”
1/8”
1/2”
3/4”
1/8”
1/2”
3/4”
1/8”
1/2”
3/4”
NPT
3/4”
3/4”
3/4”
3/4”
3/4”
3/4”
3/4”
3/4”
3/4”
3/4”
3/4”
3/4”
AWTS
AWTS
AWTS
AWTD
AWTD
AWTD
AWTT
AWTT
AWTT
AWTR
AWTR
AWTR
Single / 2
Single / 2
Single / 2
Double / 4
Double / 4
Double / 4
Triple / 6
Triple / 6
Triple / 6
RTD / 6
RTD / 6
RTD / 6
Height
3.4” or 86.4 mm
Width
3.1” or 78.7 mm
Cap Diameter
3.3” or 83.8 mm
NEMA Rating -
Type 4
AFTH
2
Thermocouple Heads - Aluminum
Manufacturing, Engineering and Sales Since 1938
Phone: 617.527.4385 Fax: 617.964.3746 Email:
sales@asrichards.comACH
Page 139
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