07/05
Semiconductor (A) fuses
Semiconductor (AC) fuses
SCAC12
American Round Fuses
Form 101 Range
A50QS
A50QS Amp-trap®Form 101 fuses grew out of the need to improve
the overall performance of semiconductor fuses in response to new
equipment requirements. The A50QS encompasses the best
protection features - lower I2t to provide better protection for
equipment, longer life when subjected to cyclic loading and lower
watts loss. A50QS is today's best choice for the protection of dynam-
ic solid state equipment such as motor drives, inverters, UPS, etc
• AC: 35-60A
500VAC, 200kA I.R.
70-1200A
500VAC, 200kA I.R.
• DC: 35-1200A
500VDC,100kA I.R.
Ratings
Features/Benefits
• Lowest l2t for greatest protection of semiconductor circuits
• low watt loss for cooler operation
• Superior cycling ability gives an equipment design advantage
• State of the art protection for 500 volt equipment
• ultra compact sizes allow down-sizing of existing equipment
• UL Recognized
Component
• AC: UL Guide No.
JFHR2
• DC Tested to UL
Standard 198L
parameters (70-1200A)
• CSA Certified
LR12636
Approvals Highlights
• 500V AC/DC Rated
• Lowest l2t
• Low Watts Loss
• Superior Cycling
Ability
Applications
• Protection of 500V
or less motor drives,
UPS, inverters, etc.
A50 QS 250 - 4
Amp-trap®Fuse
Rated Volts - 500
Style
Amperes*
Mounting Types*
Blades, bolt-in
* For ampere ratings and types not listed,
call Technical services.
Catalog Numbering System
A
50
QS
250
4
Single Pole Fuse Blocks
for A50QS Fuses
Fuse Fuse block
Ampere Mounting Catalog Reference
Rating type Number Number
35-200 4 P243E X222016
225-600 4 P266C K212897
Semiconductor Protection Fuses
12/04
CORRECTION FACTOR FOR WATTS LOSS
American Round Fuses
Form 101 Range
A50QS
SCAC13
Semiconductor (A) fuses
Semiconductor (AC) fuses
Ampere Catalog Reference Ampere Catalog Reference
Rating Number Number Rating Number Number
Standard Fuse Ampere Ratings, Catalog Numbers
For ampere ratings and styles not listed, call Technical Services.
35 A50QS35-4 Q214834 250 A50QS250-4 W211251
40 A50QS40-4 Y215853 300 A50QS300-4 D212799
50 A50QS50-4 W217392 350 A50QS350-4 T215343
60 A50QS60-4 A218937 400 A50QS400-4 B216362
70 A50QS70-4 B222664 450 A50QS450-4 E216871
80 A50QS80-4 L201513 500 A50QS500-4 L218418
90 A50QS90-4 X211252 600 A50QS600-4 Q219457
100 A50QS100-4 A216361 700 A50QS700-4 N223181
125 A50QS125-4 K218417 800 A50QS800-4 C202287
150 A50QS150-4 P219456 900 A50QS900-4 R212282
175 A50QS175-4 A222663 1000 A50QS1000-4 V217391
200 A50QS200-4 T200968 1200 A50QS1200-4 C217904
225 A50QS225-4 K201512
Ampere Watts Ampere Watts
Rating Loss (W) Rating Loss (W)
35 6 250 41
40 7 300 49
50 8 350 57
60 10 400 65
70 12 450 69
80 14 500 77
90 15 600 92
100 17 700 110
125 21 800 130
150 25 900 140
175 29 1000 160
200 33 1200 175
225 37
Dimensions
Catalog Mounting Dimensions - Inches (mm)
Number Type A B C D E F G H
A50QS35 to 100 4 3.63 1.00 2.13 2.94 2.75 0.31 0.75 0.13
(92.2) (25.4) (54.1) (74.7) (69.9) (7.9) (19.1) (3.3)
A50QS125 to 200 4 3.63 1.22 2.13 2.94 2.81 0.31 1.00 0.19
(92.2) (31.0) (54.1) (74.7) (71.4) (7.9) (25.4) (4.8)
A50QS225 to 400 4 4.34 1.50 2.09 3.41 2.78 0.41 1.00 0.25
(110) (38.1) (53.1) (86.6) (70.6) (10.4) (25.4) (6.4)
A50QS450 to 600 4 4.47 2.00 2.22 3.53 2.91 0.41 1.50 0.25
(114) (50.8) (56.4) (89.7) (73.9) (10.4) (38.1) (6.4)
A50QS700 to 800 4 6.47 2.50 2.22 5.00 3.44 .53 1.50 .25
(164.3) (63.5) (56.4) (127.0) (87.3) (13.5) (38.1) (6.4)
A50QS900 to 1200 4 6.97 3.00 3.22 5.47 4.47 .63 2.38 .44
(177.0) (76.2) (81.8) (138.9) (113.5) (15.9) (60.3) (11.1)
PERCENT RATED CURRENT
Watts Loss vs. Percent Rated Current
Watts Loss at Rated Current
Correction factor example:
At 80% rated current, watts loss equals .
54 times watts loss at rated current.
Semiconductor Protection Fuses
12/04
Semiconductor (A) fuses
Semiconductor (AC) fuses
SCAC14
American Round Fuses
Form 101 Range
A50QS
A50QS35 to 1200
CIRCUIT VOLTAGE (VOLTS RMS)
MAXIMUM PEAK ARC VOLTS
Maximum Arc Volts vs.
System Voltage
Melting Time – Current Data, 500V Fuses
AVAILABLE CURRENT IN RMS SYMMETRICAL AMPERES
MAXIMUM INSTANTANEOUS PEAK LET-THRU AMPERES
Peak Let-Thru Current Data – A50QS35 to 1200, 500 Volts AC
TIME IN SECONDS
CURRENT IN AMPERES
Semiconductor Protection Fuses
12/04
American Round Fuses
Form 101 Range
A50QS
SCAC15
Semiconductor (A) fuses
Semiconductor (AC) fuses
Semiconductor Protection Fuses
I2t Data – 500 Volts AC
35
40
50
60
70
80
90
100
125
150
175
200
225
250
300
350
400
450
500
600
700
800
900
1000
1200
Fuse
Ampere
Rating
Melting
I2t
(A2s X 103)
I2t data
Max Clearing I2t @ 500 VAC
.09
.11
.18
.25
.31
.43
.57
.74
.94
1.5
2.5
3.3
4.1
4.9
9.2
15
16
21
26
37
53
72
98
112
200
1 fuse (fig A)
(A2s X 103)
2 Fuses in series
(A2s X 103)(fig B)
.56 .34
.69 .4
1.1 .68
1.6 .94
1.9 1.1
2.6 1.5
3.6 2.1
4.4 2.7
5.6 3.4
9 5.4
15 9
20 12
25 15
29 18
55 33
88 53
98 59
130 76
160 94
220 130
270 160
360 220
500 300
560 330
930 550
35
40
50
60
70
80
90
100
125
150
175
200
.48
.58
1.0
1.3
1.6
2.2
3.0
3.8
4.8
7.7
13
17
250
300
350
400
450
500
600
700
800
900
1000
1200
25
47
75
83
110
130
190
220
260
350
430
660
Ampere
Rating
Clearing I2t
(A2s X 103)
Ampere
Rating
Clearing I2t
(A2s X 103)
Clearing I2t at 500V DC,
100kA, L/R = 10 ms
DC Application: A50QS Fuses have been designed for
both AC and DC operation. A50QS fuses (70-600) have
UL Component Recognition at 500V DC and have been
tested to circuit parameters as defined in Standard 198L.
OPERATING VOLTAGE (AC RMS VOLTS)
CORRECTION FACTOR FOR I2T
Clearing I2t vs. AC Operating Voltage
Load
500 VAC Fault
Fig. A
Load
500 VAC Fault
Fig. B
L/R TIME CONSTANT (MS)
DC Voltage Capability vs. Time Constant
DC VOLTAGE CAPABILITY
