www.vishay.com For technical questions, contact: ww2bresistors@vishay.com Document Number: 30201
4Revision: 02-Mar-11
RH, NH
Vishay Dale Wirewound Resistors, Industrial Power,
Aluminum Housed, Chassis Mount
MATERIAL SPECIFICATIONS
Element: Copper-nickel alloy or nickel-chrome alloy,
depending on resistance value
Core: Ceramic, steatite or alumina, depending on physical
size
Encapsulant: Silicone molded construction
Housing: Aluminum with hard anodic coating
End Caps: Stainless steel
Standard Terminals: For RH005 through RH050 size
terminal finish - Tin/lead is 60/40 Sn/Pb w/Nickel underplate
and Lead (Pb)-free is Ni/Pd/Au, finish is on copper clad
steel core terminal. For RH100 and RH250 terminals are
threaded stainless steel.
Part Marking: Dale, model, wattage, value, tolerance, date
code
NH NON-INDUCTIVE
Models of equivalent physical and electrical specifications
are available with non-inductive (Aryton-Perry) winding.
They are identified by substituting the letter N for R in the
model number (NH005, for example).
SPECIAL MODIFICATIONS
A number of special modifications to the aluminum housed
resistor style are available upon request. Special
modifications include:
•Terminal configurations and materials
•Resistance values and tolerances
•Low resistance temperature coefficient (RTC)
•Housing configuration
•Threaded mounting holes
•Preconditioning and other additional testing
APPLICABLE MIL SPECIFICATIONS
Vishay RH and NH resistors are listed as qualified on the
MIL-PRF-18546 QPL. MIL-PRF-18546 qualified, type RE
resistors can be found at: www.vishay.com/doc?30282
PERFORMANCE
TEST CONDITIONS OF TEST TEST LIMITS
Thermal Shock Rated power applied until thermally stable, then a minimum of 15 min at - 55 °C ± (0.5 % + 0.05 ) R
Short Time Overload 5 x rated power for 5 s ± (0.5 % + 0.05 ) R
Dielectric Withstanding
Voltage
1000 Vrms for RH005, RH010 and RH025; 2000 Vrms for RH050;
4500 Vrms for RH100 and RH250; duration 1 min ± (0.2 % + 0.05 ) R
Temperature 250 °C for 2 h ± (0.5 % + 0.05 ) R
Moisture Resistance MIL-STD-202 Method 106, 7b not applicable ± (1.0 % + 0.05 ) R
Shock, Specified Pulse MIL-STD-202 Method 213, 100 g’s for 6 ms, 10 shocks ± (0.2 % + 0.05 ) R
Vibration, High Frequency Frequency varied 10 Hz to 2000 Hz, 20 g peak, 2 directions 6 h each ± (0.2 % + 0.05 ) R
Load Life 1000 h at rated power, + 25 °C, 1.5 h “ON”, 0.5 h “OFF” ± (1.0 % + 0.05 ) R
Terminal Strength 30 s, 5 pound pull test for RH005 and RH010, 10 pound pull test for other sizes;
torque test - 24 pound inch for RH100 and 32 pound inch for RH250 ± (0.2 % + 0.05 ) R