Caddock
Current Sense Resistors
654
b
ALLIED See Our Manufacturer Index Located In Section 1
Type SR Precision Current Sense Resistors,
Kelvin Terminals, 0.008 ½ to 1.00 ½, 1.0 and
2.0 Watt Versions
Standard Tolerance: 1%. Temperature Coefficient. TC taken at Ð15¡C and 105¡C;
0.081 ohms and above, Ð50 to +100 ppm/¡C; below 0.081 ohms down to 0.025 ohm, 0 to
+150 ppm/¡C; below 0.025 ohm down to 0.008 ohm, 0 to +200 ppm/¡C. Load Life:
1000 hours at rated power at 70¡C ÆR 0.2% max.
*Power Rating: The power rating should be limited as
shown by the derating curve based upon the maximum
ambient temperature. The derating curve is based on still
air with natural convection around the resistor.
Measurement Note: For purposes of these specifications,
resistance measurement shall be made using Kelvin connections (four wire) with
appropriate current and sense connections to the device terminals.
Circuit Board Layout: The circuit board traces connecting to the current terminals must be
sized appropriately for the current flowing through the trace to avoid excessive heating of
the trace. For example; 0.008 ½ operated at 1.0 watts would have 11.2 amps flowing
through the circuit board traces into the current terminals.
524-4120 SR10 1% 0.008 1.0 Watt* Power Ltd. 0.008 3.202.912.67
524-4122 SR10 1% 0.010 1.0 Watt* Power Ltd. 0.010 3.202.912.67
524-4124 SR10 1% 0.015 1.0 Watt* Power Ltd. 0.015 3.202.912.67
524-4126 SR10 1% 0.020 1.0 Watt* Power Ltd. 0.020 2.77 2.52 2.31
524-4128 SR10 1% 0.025 1.0 Watt* Power Ltd. 0.025 2.77 2.52 2.31
524-4130 SR10 1% 0.030 1.0 Watt* Power Ltd. 0.030 2.77 2.52 2.31
524-4132 SR10 1% 0.033 1.0 Watt* Power Ltd. 0.033 2.77 2.52 2.31
524-4134 SR10 1% 0.040 1.0 Watt* Power Ltd. 0.040 2.77 2.52 2.31
524-4136 SR10 1% 0.050 1.0 Watt* Power Ltd. 0.050 2.77 2.52 2.31
524-4138 SR10 1% 0.075 1.0 Watt* Power Ltd. 0.075 2.77 2.52 2.31
524-4140 SR10 1% 0.10 1.0 Watt* Power Ltd. 0.100 2.77 2.52 2.31
524-4142 SR10 1% 0.20 1.0 Watt* Power Ltd. 0.200 2.77 2.52 2.31
524-4144 SR10 1% 0.25 1.0 Watt* Power Ltd. 0.250 2.77 2.52 2.31
524-4146 SR10 1% 0.40 1.0 Watt* Power Ltd. 0.400 2.77 2.52 2.31
524-4148 SR10 1% 0.50 1.0 Watt* Power Ltd. 0.500 2.77 2.52 2.31
524-4150 SR10 1% 0.75 1.0 Watt* Power Ltd. 0.750 2.77 2.52 2.31
524-4152 SR10 1% 1.00 1.0 Watt* Power Ltd. 1.000 2.77 2.52 2.31
524-4160 SR20 1% 0.008 2.0 Watts* Power Ltd. 0.008 4.79 4.36 4.00
524-4162 SR20 1% 0.010 2.0 Watts* Power Ltd. 0.010 4.79 4.36 4.00
524-4164 SR20 1% 0.015 2.0 Watts* Power Ltd. 0.015 4.79 4.36 4.00
524-4166 SR20 1% 0.020 2.0 Watts* Power Ltd. 0.020 4.16 3.78 3.47
524-4168 SR20 1% 0.025 2.0 Watts* Power Ltd. 0.025 4.16 3.78 3.47
524-4170 SR20 1% 0.030 2.0 Watts* Power Ltd. 0.030 4.16 3.78 3.47
524-4172 SR20 1% 0.033 2.0 Watts* Power Ltd. 0.033 4.16 3.78 3.47
524-4174 SR20 1% 0.040 2.0 Watts* Power Ltd. 0.040 4.16 3.78 3.47
524-4176 SR20 1% 0.050 2.0 Watts* Power Ltd. 0.050 4.16 3.78 3.47
524-4180 SR20 1% 0.10 2.0 Watts* Power Ltd. 0.100 4.16 3.78 3.47
524-4182 SR20 1% 0.20 2.0 Watts* Power Ltd. 0.200 4.16 3.78 3.47
524-4184 SR20 1% 0.25 2.0 Watts* Power Ltd. 0.250 4.16 3.78 3.47
524-4186 SR20 1% 0.40 2.0 Watts* Power Ltd. 0.400 4.16 3.78 3.47
524-4188 SR20 1% 0.50 2.0 Watts* Power Ltd. 0.500 4.16 3.78 3.47
524-4190 SR20 1% 0.75 2.0 Watts* Power Ltd. 0.750 4.16 3.78 3.47
524-4192 SR20 1% 1.00 2.0 Watts* Power Ltd. 1.000 4.16 3.78 3.47
ÑÑÑÑÑ4.16 3.78 3.47
Visit CaddockÕs Website at www.caddock.com
11
524-5XXX MK 132 .75 400 1 - 20 5.77 5.25 4.81
50 3.61 3.28 3.01
100 - 50K 3.00 2.73 2.50
100K - 500K 3.61 3.28 3.01
1 M - 5 M 4.67 4.25 3.89
524-5XXX MK 632 .75 400 10 M 4.96 4.51 4.13
20 M 5.96 5.42 4.96
50 M - 100 M 5.96 5.42 4.96
Comparison of Type MK and ÒRNÓ Ratings and Dimensions
This table of ÒRNÓ style axial-lead resistors shows the many sizes and power ratings that
can be replaced with one of the type MK precision film resistors within the maximum
allowable voltage ratings.
Mounting
Resistor Power Maximum Hole
Type Rating Resistance Spacing
MK 132 .75W 100 Megohms .200
or MK 632 (5.08)
RN50 .05W 1 Megohm .400
(10.15)
RN55 .10W 5 Megohms .500
(12.70)
RN60 .125W 10 Megohms .625
(15.90)
RN65 .25W 20 Megohms .875
(22.20)
RN70 .50W 40 Megohms 1.000
(25.40)
Type MK Radial Lead Precision Power Resistor, CK06 Size,
1 Ohm to 100 Meg, 0.75 Watt Rating
Standard Tolerance: 1%. Temperature Coefficient: 5 ohm to 5 Meg, ±50 ppm/¡C; <5 ohm
±200 ppm/¡C; >5 Meg, ±80 ppm/¡C; TC referenced to +25¡C, ÆR taken at Ð15¡C and
+105¡C. Operating Temperature: Ð55¡C to +175¡C, 100% rated power at +125¡C derated
linearly to zero at +175¡C. Leadwire: Tinned copper.
Stock Mfr.Õs Wattage Max. Ohms/
No. Type 125¡C Voltage Range
EACH
1-9 10-24 25-49
Ohms XX Ohms XX Ohms XX Ohms XX Ohms XX Ohms XX
1
5
20
50
100K
200K
500K
1M
2M
5M
10M
20M
2K
10K
20K
50K
100
200
500
1K
020
050
098
158
905
906
924
935
50M
100M
Ñ
Ñ
950
975
Ñ
Ñ
202
243
306
356
400
522
575
655
717
759
627
877
Stock Mfr.Õs Power Max. Ohms
No. Type Rating Voltage
EACH
1-9 10-24 25-49
Stock Mfr.Õs Power Max. Ohms
No. Type Rating Voltage
EACH
1-9 10-24 25-49
