RESISTORS

Air Cooled High Power Non-Reactive Cermet Resistors Type A Power Film Systems

TYPE A

High Power Non-Reactive Cermet Resistors

WATER COOLED

  • Wide resistance range
  • Power ratings to 300kW* (up to 1,000 watts per square inch)
  • Extremely durable
  • Very low TCR: 100 ppm typical
  • Very stable: less than .4% change after 10 hours at rated power
  • Resistor is directly cooled by water (I.D. and O.D.)
  • Typical VSWR 1.1 to 1*
  • Low cost alumina substrate: power dissipation exceeds resistors built on BeO substrate and cooled from one side
  • Used by most water cooled RF termination manufacturers.

* In a properly designed system with proper water flow. Consult factory

 

Max. size 4.0″ OD x 40″ Long
Dimensions (Inches)
Type No.
Rated Power (Watts)**
A
B
C
D
PFS 5
5,000
.500
.375
5.00
.375
PFS 7.5
10,000
.875
.500
7.625
.625
PFS 12
50,000
1.1
.500
12.00
.875
PFS 34
100,000
1.1
.500
34.00
.875

TYPE CP

High Power Non-Reactive Cermet Resistors

AIR COOLED

  • Standard size 10 watts to 1,000 watts in static air
  • VERY HIGH POWER DISSIPATION
  • Wide resistance range: 1 ohm to 20 meg ohms
  • High stability
  • Low TCR: less than 300 ppm typical
  • Superior terminals: platinum/silver offers much lower contact resistance than nickel or aluminum
  • Excellent moisture resistance
  • Excellent RF characteristics
  • May be used in place of other types of resistors
  • Close tolerances available

 

Watts at 40°C Derated to Zero
Ambient* at 350°C
Standard Sizes (Other Sizes Available)
Max. Size 4.0″ OD x 40″ Long
Dimensions (Inches)
Type No.
Rated Power (Watts)**
A
B
C
D
PFS 1.75
10
.500
.250
1.75
.250
PFS 2
20
.500
.250
2.00
.250
PFS 2.5
30
.750
.500
2.50
.250
PFS 5
60
.750
.500
5.00
.500
PFS 6
100
1.0
.750
6.00
.750
PFS 8
150
1.0
.750
8.00
.750
PFS 12
300
1.0
.750
12.00
.750
PFS 18
500
1.0
1.0
18.00
.750
PFS 18
750
2.0
1.0
18.00
1.75
PFS 24
1000
2.0
1.0
24.00
1.75
Air Cooled High Power Non-Reactive Cermet Resistors Type A1

TYPE A1

High Power Non-Reactive Cermet Resistors

INTERNAL WATER COOLED

  • Convenient hose connections
  • Custom design to application
  • Small size
  • Call for application
 

Dimensions (Inches)
Type No.
Rated Power (Watts)**
A
B
C
D
PFS 5
325
.500
.500
5.00
.375
PFS 6
800
1.0
.750
6.00
.750
PFS 8
1067
1.0
.750
8.00
.750
PFS10
1200
1.0
.750
10.00
.750

TYPE O

Non-Reactive Cermet Resistors

OIL COOLED

  • Call for application

 

Dimensions (Inches)
Type No.
Rated Power (Watts)**
A
B
C
D
PFS 10
50w/in2
.500
.375
10.00
.375
PFS 17.25
50w/in2
.625
.375
17.25
.500

TYPICAL SPECIFICATIONS

Type A
Type A1
Type O
Type CP
Resistance Range
1ohm-20meg ohms
Same
Tolerances
20%-10%-5%-2%-1%
Same
Load Life
Max. 5% change after 1000hrs at rated load
Same
Short Time Overload (10 times rated. Power 5 seconds on -90 seconds off)
2% change
Same
Temperature Coefficient (per degree C)
300 ppm Max.
Same
Voltage Coefficient
Max. 1%-KV/IN
Same
Maximum Operating Temperature
90°C+
<100°C+
++
350°C*
Moisture Resistance
2.5% change Mil Std 202B, Method 103
Same
Standard Metalization
Pt/Ag (Au/Pt. Pd/Ag optional)
Same

+Cavitation begins at 90oC disrupting water flow.
++Maximum operating temperature Mineral Oil 125oC/Silicon Oil 250oC

Typical VSWR Most Applications Obtain 1.1 to 1