PFE and PFR Series
Powr-Rib® Edgewound
Edgewound and Round Wire
Designed in both Edgewound and Round
Wire formats, these rugged resistors can
handle 700 to 1000 Watts of power.
Specify our Edgewound design for
very low resistance and high power
capacity. When higher resistance with lower power
capacity is required use our Round Wire design.
These resistors are constructed of a heavy resistance alloy mounted on
ceramic insulators and supported by a metal mounting bracket. Metal parts,
except for the resistance element, are heavily plated to prevent oxidation at high
operating temperatures and to prevent corrosion. The mounting bar is slotted
on each end to facilitate installation. Edgewound units provide clamp-type ter-
minals, permitting a reliable connection which can be moved along the resistive
element to obtain intermediate values.
chꢀRꢀctERꢁStꢁcS
Size* (No. of
Continuous duty as listed on follow-
ing page.
Current Rating
Wattage Rating
Insulator-Sections Long)
2
3
4
5 (std.)
6
7
8
Dimension A
Dimension B
in.
mm
8.875
11.875 14.875 17.875 20.875 23.875 26.875
700 to 1,000 (up to 1,600 watts on
special order)
(225.43) (301.63) (377.83) (454.03) (530.23) (606.43) (682.63)
in.
mm
7.250
10.250 13.250 16.250 19.250 22.250 25.250
(184.15) (260.35) (336.55) (412.75) (488.95) (565.15) (641.35)
±10% standard, ±5% available
Resistance
Tolerance
Max. Amps Ohms
Ohms
Ohms
Ohms
Ohms
Ohms
Ohms
Clamps, movable along resistor
wire for setting intermediate resis-
tance values on Edgewound units
(current must be derated in propor-
tion).
Terminals
PFE Edgewound
100
91
89
78
75
0.033
0.040
0.046
0.052
0.060
0.057
0.070
0.078
0.088
0.100
0.080
0.100
0.110
0.120
0.140
0.100
0.120
0.140
0.160
0.180
0.120
0.140
0.170
0.190
0.210
0.140
0.160
0.200
0.220
0.250
0.160
0.180
0.230
0.250
0.300
68
63
57
54
50
0.070
0.080
0.100
0.110
0.120
0.120
0.130
0.160
0.180
0.200
0.180
0.190
0.230
0.250
0.280
0.220
0.250
0.300
0.330
0.370
0.260
0.300
0.360
0.400
0.450
0.300
0.350
0.420
0.470
0.530
0.340
0.400
0.480
0.540
0.610
±300 ppm/°C for resistors 50 amps
and more; ±500 ppm/°C for resis-
tors 47 amps or less
Temperature
Coefficient
See chart on following page
Ohmic Values
Mounting
47
43
41
39
33
0.170
0.210
0.230
0.260
0.350
0.280
0.330
0.360
0.420
0.560
0.380
0.460
0.510
0.580
0.770
0.500
0.600
0.670
0.750
1.00
0.600
0.720
0.800
0.900
1.20
0.700
0.850
0.930
1.05
0.800
0.980
1.06
Metal mounting bar is slotted on
each end to facilitate installation.
1.20
1.40
1.60
10x rated wattage for five seconds
Short Term
Overload
29
26
18.4
16.3
14.6
0.450
0.560
0.690
0.880
1.10
0.730
0.900
1.20
1.50
1.90
1.00
1.20
1.70
2.20
2.70
1.30
1.60
2.20
2.80
3.50
1.50
1.90
2.70
3.40
4.30
1.75
2.20
3.10
4.00
5.10
2.00
2.50
3.50
4.60
5.90
Derating
12.7
11.8
10.3
9.4
1.40
1.70
2.10
2.70
2.40
2.90
3.70
4.60
3.50
4.20
5.30
6.50
4.50
5.40
6.80
8.50
5.50
6.60
6.50
7.80
9.80
12.3
7.50
9.00
11.3
14.2
100
80
60
40
20
0
8.30
10.40
PFR Round-Wire
8.3
7.6
6.6
5.9
5.1
3.4
4.1
5.3
6.3
7.9
5.9
7.1
8.5
11.0
13.0
17.0
20.0
25.0
13.5
15.9
20.8
24.5
30.7
16.0
18.8
24.6
29.0
36.4
18.5
21.7
28.4
33.5
42.1
10.0
13.0
15.4
19.3
9.2
10.9
13.6
*Standard 5-section units are stocked; part numbers are listed on the following page.
0 2550 100 150 200 250 300 350
Ambient Temperature, °C
(continued)
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