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LET-British BS 88 240V 25-180A

Description: BS 88 style stud-mount high speed semiconductor fuses.
Dimensions: See dimensions illustrations.

Volts: 240Vac/150Vdc
Amps: 25-180A
IR: 200kA RMS Sym.
Agency Information: CE, Designed and tested to: BS 88 Part 4, IEC 269 Part 4, UL Recognized. All fuses above have been tested at 318Vac. Consult Cooper Bussmann for specific UL Recognition status.

Electrical Characteristics
Total Clearing I2t

The total clearing I2t at rated voltage and at power factor of 15% are given in the electrical characteristics. For other voltages, the clearing I2t is found by multiplying by correction factor, K, given as a function of applied working voltage, Eg, (rms).

Dimensions (mm)

Arc Voltage

This curve gives the peak arc voltage, UL, which may appear across the fuse during its operation as a function of the applied working voltage, Eg, (rms) at a power factor
of 15%.

Power Losses

Watts loss at rated current is given in the electrical characteristics. The curve allows the calculation of the power losses at load currents lower than the rated current. The correction factor, Kp, is given as a function of the RMS load current, Ib, in % of the rated current.

Catalog Numbers
Catalog Numbers Type Rated Current RMS-Amps I2t(A2 Sec) Watts Loss
Pre-arc Clearing
at 120V at 240V
25LET LET 25 18 120 250 4
32LET 32 32 200 450 5
35LET 35 50 320 600 5
50LET 50 100 500 1400 7
63LET 63 180 1100 2200 9
80LET 80 300 1900 3800 10
100LET 100 600 3800 7500 10
125LET 125 600 3800 7500 16
160LET 160 1100 7000 16000 20
180LETa 180 1600 1200 29000 21
• Watts loss provided at rated current.
• Note: 7LET, 10LET, 12LET and 16LET are available for replacement purposes on existing equipment.

Features and Benefits
• Excellent cycling capability
• Excellent DC performance
• Low arc voltage and low energy let-through (I2t)

Typical Applications
• DC common bus
• AC and DC drives
• Power converters/rectifiers
• Reduced voltage starters

Time-Current Curve

Peak Let-Through Curve