Electrical Characteristics
Features
■72 V rated
■Radial leaded devices
■Cured, flame retardant epoxy polymer
insulating material meets
UL 94V-0 requirements
■RoHS compliant*
■Agency recognition:
Applications
Almost anywhere there is a low voltage
power supply, up to 72 V and a load to be
protected, including:
■Security and fire alarm systems
■Loudspeakers
■Power transformers
1 Hour (R1)Max. Time Tripped
Ihold Itrip Initial Post-Trip To Trip Power
Resistance Resistance Dissipation
Model Amperes Ohms Ohms Amperes Seconds Watts
V max. I max.
at 23 °C at 23 °C at 23 °C at 23 °C at 23 °C at 23 °C
Volts Amps
Hold Trip Min. Max. Max. Typ.
MF-RX110/72 72.0 40 1.10 2.20 0.15 0.25 0.38 5.5 8.2 1.50
MF-RX135/72 72.0 40 1.35 2.70 0.12 0.19 0.30 6.75 9.6 1.70
MF-RX160/72 72.0 40 1.60 3.20 0.09 0.14 0.22 8.0 11.4 1.90
MF-RX185/72 72.0 40 1.85 3.70 0.08 0.12 0.19 9.25 12.6 2.10
MF-RX250/72 72.0 40 2.50 5.00 0.05 0.08 0.13 12.5 15.6 2.50
MF-RX300/72 72.0 40 3.00 6.00 0.04 0.06 0.10 15.0 19.8 2.80
MF-RX375/72 72.0 40 3.75 7.50 0.03 0.05 0.08 18.75 24.0 3.20
Operating/Storage Temperature ........................-40 °C to +85 °C
Maximum Device Surface Temperature
in Tripped State ................................................125 °C
Passive Aging......................................................+85 °C, 1000 hours ....................................±5 % typical resistance change
Humidity Aging....................................................+85 °C, 85 % R.H. 1000 hours ..................±5 % typical resistance change
Thermal Shock....................................................+85 °C to -55 °C, 10 times ........................±10 % typical resistance change
Solvent Resistance ............................................MIL-STD-202, Method 215 ........................No change
Vibration ..............................................................MIL-STD-883C, Method 2007.1, ................No change
Condition A
Environmental Characteristics
Test Test Conditions Accept/Reject Criteria
Visual/Mech. ......................................................Verify dimensions and materials ................Per MF physical description
Resistance ..........................................................In still air @ 23 °C........................................Rmin ≤R ≤Rmax
Time to Trip ........................................................5 times Ihold, Vmax, 23 °C ........................T ≤max. time to trip (seconds)
Hold Current ......................................................30 min. at Ihold ..........................................No trip
Trip Cycle Life ....................................................Vmax, Imax, 100 cycles ..............................No arcing or burning
Trip Endurance....................................................Vmax, 48 hours ..........................................No arcing or burning
UL File Number ..................................................E 174545S
Test Procedures And Requirements For Model MF-RX/72 Series
*RoHS Directive 2002/95/EC Jan 27 2003 including Annex
Specifications are subject to change without notice.
Customers should verify actual device performance in their specific applications.