5
FIREROD® Product Guide
Notes:
1) Above depictions represent the basic protection requirements in a simple circuit.
2) Multiple heating elements may be wired in series or parallel.
3) Heating elements considered “live” must be isolated from protective ground circuit.
The tables below list standard specifications for the preferred lead wires for the product.
Note:
not all lead wire
options are shown below, please reference descriptions in your quote and/or purchase order for additional or
non-standard lead wire specifications.
Note:
lead wires should not be assumed to be agency recognized unless marked as such. Contact your Watlow
representative if you have further questions.
Product Size Designation
Heater Sheath Nominal Outer Diameter
3.1 < 9.4 mm
(
1
/
8
-
5
/
16
in.)
9.4 < 12.6 mm
(
3
/
8
and
7
/
16
in.)
12.6 < 15.8 mm
(
1
/
2
and
9
/
16
in.)
≥ 15.8 mm
(≥
5
/
8
in.)
Fiberglass insulated
24 Ga. MGT 300V 22 Ga. MGT 300V 18 Ga. MGT 300V 18 Ga. MGT 600V
PTFE insulated
24 Ga. black
PTFE 300V
22 Ga. black
PTFE 300V
18 Ga. black
PTFE 300V
14 Ga. black
PTFE 600V
Minimum Recommended Circuit Requirements
(AC - Three Phase Delta)
Standard/Default Lead Wires
Product Size Designation
Heater Sheath Nominal
Outer Diameter
3.1 < 9.4 mm
(
1
/
8
-
5
/
16
in.)
9.4 < 12.6 mm
(
3
/
8
and
7
/
16
in.)
12.6 < 15.8 mm
(
1
/
2
and
9
/
16
in.)
≥ 15.8 mm
(≥
5
/
8
in.)
Alternate
≥ 15.8 mm
(≥
5
/
8
in.)
Recognition
UL
®
5128 / CSA
UL
®
5107 / CSA
Max voltage
300 Volts
600 Volts
Strands
7/32
7/30
7/26
7/26
41/30
Design description
24 Ga. MGT
nickel leads
22 Ga. MGT
nickel leads
18 Ga. MGT
nickel 300V
18 Ga. MGT
nickel 600V
14 Ga. MGT
nickel leads
Max amperage
3.1
4.4
7.6
7.6
12.5
Design description
24 Ga. MGT NCC
leads
22 Ga. MGT NCC
leads
18 Ga. MGT NCC
300V
18 Ga. MGT NCC
600V
14 Ga. MGT NCC
leads
Max amperage
5.2
7.2
12.6
12.6
21.0
Fiberglass Lead Wire Specifications
MGT fiberglass lead wire maximum temperature = 842°F (450°C)
Minimum Circuit Requirements (Con’t)
