3R-250
250Watt Mountable Non-Inductive,
High Frequency Resistors
Motor Controls, High Energy, RF, High Voltage, Inverters, Pulse & Plasma,
Non-Inductive Powers
3R-250 Non-Inductive design these elements are ideally suites for high frequency and pulse load applications. By direct
mounting on a heatsink significant cost advantages can be reailzed for power Appliation from 100w to 600w. 3R-250 can
be supplied in a 2-terminal Main applications are Variable speed Drives, ship, train, RF Termination, Power Supplies, Control
Devices, Telecom, Robotics, Motor Controls Dynamic Braking, and other switching designs.
3R-250 Non-Inductive 250Watt
Mountable, High Frequency Resistors
·Heat Sink Mountable
with M4 Screw
·RF Terminal
·Shunt
·Inverter
·Moter Braking
·Pulse & Plasma
S
PECIFICATIONS
Resistance Values :
1R0 to 2Megohm others on
rquest
Resistance Tolerance :
± 10% Std. ,1%,2%,5%
available on request.
Temperature Coefficient :
± 100ppm/°C typ.
(others upon request)
Maximum Working Voltage :
5,000V DC, higher
voltage on request, not execeeding max. power
Single Shot Voltage :
Up to 12kV at std. wave
(1.5/50
㎲)
Insulation Resistance :
10GΩ min. at 500V
Creeping Distance :
42mm min.
Inductance :≤50
nH
Capacity/Ground :
≤110pF
Capacity/Resistive :
≤40pF
Operation Temperature :
-55°C to +155°C
Max. Torque for Contacts :
2 N.m
Max. Torque for Mounting :
1.8 N.m
Power Rating :
250W at 50°C Tap Temperature
Higher power :
600Watt at 5°C Tap Temperature
Dielectric Strength :
Up to 12 kV
Termination to Contacts :
M5 Screws
Required thermal transfer compound of-heat
conductivity :
1 W/°C
Required flatness of heat sink :
≤ 0.05mm
Roughness of the Heatsink surface :
≤ 6.4㎛.
Isolation Voltage(Terminal to Heatsink) :
7k Vrms
cf.: The described specifications & dimensions subject to change without notice.
D
IEMENSION
D
ERATING CURVE
Rated Power or Voltage%
00
80
60
40
20
0
25
50
75
00
25
50
75
Tap Temperature (˚C)
Willow Technologies Ltd.
Shawlands Court, Newchapel Road, Lingfield, Surrey, RH7 6BL, United Kingdom.
info@willow.co.uk
http://www.willow.co.uk
+ 44 (0) 1342 835234
+ 44 (0) 1342 834306