Environmental Characteristics
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 ................................................ -40 °C to +85 °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
Test Procedures And Requirements For Model MF-RX Series
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
CSA File Number ............................................. CA 110338
TÜV File Number ............................................. R2057213
Electrical Characteristics
Model V max.
Volts
I max.
Amps
Ihold
Itrip Initial
Resistance
1 Hour (R1)
Post-Trip
Resistance
Max. Time
to Trip
Tripped
Power
Dissipation
Amperes
at 23 °C
Ohms
at 23 °C
Ohms
at 23 °C
Amperes
at 23 °C
Seconds
at 23 °C
Watts
at 23 °C
Hold Trip Min. Max. Max. Typ.
MF-RX110 60 40 1.10 2.20 0.15 0.25 0.38 5.5 8.2 1.50
MF-RX135 60 40 1.35 2.70 0.12 0.19 0.30 6.75 9.6 1.70
MF-RX160 60 40 1.60 3.20 0.09 0.14 0.22 8.0 11.4 1.90
MF-RX185 60 40 1.85 3.70 0.08 0.12 0.19 9.25 12.6 2.10
MF-RX250 60 40 2.50 5.00 0.05 0.08 0.13 12.5 15.6 2.50
MF-RX300 60 40 3.00 6.00 0.04 0.06 0.10 15.0 19.8 2.80
MF-RX375 60 40 3.75 7.50 0.03 0.05 0.08 18.75 24.0 3.20
Features
■ Radial Leaded Devices
■ Cured, fl ame retardant epoxy polymer
insulating material meets UL 94V-0
requirements
■ Agency recognition:
■ RoHS compliant*
MF-RX Series - PTC Resettable Fuses
*RoHS Directive 2002/95/EC Jan 27, 2003 including Annex.
Specifi cations are subject to change without notice.
Customers should verify actual device performance in their specifi c applications.
The MF-RX Series is currently
available, although not recommended
for new designs. The higher voltage
rated MF-RX/72 Series is preferred.
Thermal Derating Chart - Ihold / Itrip (Amps)
Model Ambient Operating Temperature
-40 ºC -20 ºC 0 ºC 23 ºC 40 ºC 50 ºC 60 ºC 70 ºC 85 ºC
MF-RX110 1.71 / 3.42 1.50 / 3.00 1.31 / 2.62 1.10 / 2.20 0.89 / 1.78 0.79 / 1.58 0.69 / 1.38 0.59 / 1.18 0.44 / 0.88
MF-RX135 2.09 / 4.18 1.84 / 3.68 1.61 / 3.22 1.35 / 2.70 1.09 / 2.18 0.97 / 1.94 0.85 / 1.70 0.73 / 1.46 0.54 / 1.08
MF-RX160 2.48 / 4.96 2.18 / 4.36 1.90 / 3.80 1.60 / 3.20 1.30 / 2.60 1.15 / 2.30 1.01 / 2.02 0.86 / 1.72 0.64 / 1.28
MF-RX185 2.87 / 5.74 2.52 / 5.04 2.20 / 4.40 1.85 / 3.70 1.50 / 3.00 1.33 / 2.66 1.17 / 2.34 1.00 / 2.00 0.74 / 1.48
MF-RX250 3.88 / 7.76 3.40 / 6.80 2.98 / 5.96 2.50 / 5.00 2.03 / 4.06 1.80 / 3.60 1.58 / 3.16 1.35 / 2.70 1.00 / 2.00
MF-RX300 4.65 / 9.30 4.08 / 8.16 3.57 / 7.14 3.00 / 6.00 2.43 / 4.86 2.16 / 4.32 1.89 / 3.78 1.62 / 3.24 1.20 / 2.40
MF-RX375 5.81 / 11.6 5.10 / 10.2 4.46 / 8.92 3.75 / 7.50 3.04 / 6.08 2.70 / 5.40 2.36 / 4.72 2.03 / 4.06 1.50 / 3.00