更优异的性能指标
Fluke A40B 精密分流器包含14个低电感同轴分流器，测量电流范围从0.1mA 至100A。主要用于在实验室测量交直流电流和校准交直流电流转换测量装置。 A40B分流器的分流器内部的物理结构和元件的精密性保证了它的频率响应非常平坦，电阻值非常稳定、准确，具有出色的低自加热功率系数和低温度系数，可以用于直接测量电流从直流到100kHz，直流电流准确度达 20 ppm，交流电流准确度达 23 ppm，远远高于之前的所有分流器装置。因此，现在精密电流测量可以直接根据分流器电阻值的换算，而不一定要使用传统复杂的交直流转换转换方法了。

更广泛的应用
用A40B分流器和测量电压仪器配合使用，可以直接测量交直流电流，校准各种校准器的电流功能，支持大电流跨导放大器的校准。由于A40B相位偏移极低，这一特点对交流功率测量，尤其是非正弦波形的测量非常关键，可以在电能质量分析和数字功率表的作电流采样器获得电流信号的幅值和相位。

更灵活的使用
A40B分流器的电压输出标称值为0.8V。相对于传统的45/75 mV分流器，输出电压高，大大提高了信噪比，可以非常方便地配用精密电压表或其他测量仪器，100A电流对应的电阻为8mW，随着电阻增加到80W，电流量程为10mA。另外，1mA的分流器有内部有一个电池供电的缓冲放大器，可以驱动输出电压，使得 800W 的分流电阻与测量装置产生zui小的相互影响。
A40B分流器出厂附带着可溯源的校准报告。如客户需要，可选购符合17025A标准要求的校准报告。

Absolute accuracy
The following table shows the 1-year absolute accuracy specification stated at k=2, approximay 95 % confidence for the calibrated value. The specifications include 1-year stability, temperature effects over TCal ± 1 °C, and the measurement uncertainty of the calibrated value.
Shunt Nominal Current: Specification ± μA/A, TCal ±1 °C, ≤ 50 % RH 1,2,3,5
  DC 1 kHz 100 kHz
1 mA 20 55 150
10 mA 20 26 26
20 mA 20 26 26
50 mA 20 23 23
100 mA 20 24 24
200 mA 20 26 26
500 mA 21 27 28
1 A 21 27 31
2 A 21 27 48
5 A 21 31 71
10 A 26 37 92
20 A 26 43 113
50 A 32 55 144
100 A 35 65 174
1 The measured current is determined from: I = （V/Rcalibrated） ×
（1 + （AC-DCcalibrated/1,000,000））; where AC-DC calibrated is expressed in ppm.
2 Above 1 kHz interpolate the specification （si） between frequencies fupper and flower using:
si = slower + （fi – flower） × （supper – slower） ÷ （fupper – flower）
3 Add 20 μA/A if relative humidity is outside specification limits.
4 1 mA specifications apply with the battery charger disconnected.
5 Specifications assume no loading effects due to the voltage-sensing device. See Output Voltage Measurement – Loading Effects in the operating information. 

Maximum AC-DC Difference
Shunt Nominal Current: Maximum AC-DC Difference （± ppm）1,2
  1 kHz 100 kHz
1 mA3 53 150
10 mA 20 40
20 mA 18 30
50 mA 13 16
100 mA 14 27
200 mA 17 28
500 mA 17 21
1 A 17 23
2 A 17 44
5 A 23 69
10 A 28 98
20 A 37 150
50 A 47 180
100 A 60 300
1 Specifications indicate the maximum flatness deviation from dc, and include both measured AC-DC difference and the uncertainty of measurement. They are stated at k=2, approximay 95 % confidence.
2 Includes 1-year stability of the AC-DC difference.
3 Specifications for the 1 mA current shunt are for TCal ± 1 °C. 

General Specifications
Dimensions （maximum） Shunt Value: 1 mA to 2 A
Height: 70 mm （2.75 in）
Width: 70 mm （2.75 in）
Overall Length1:
124 mm （4.9 in）
Shunt Value: 5 A to 20 A
Height: 130 mm （5 in）
Width: 130 mm （5 in）
Overall Length1:
210 mm （8.25 in））
Shunt Value: 50 A and 100 A
Height: 200 mm （7.9 in）
Width: 200 mm （7.9 in）
Overall Length1:
343 mm （13.5 in））
1 Includes input and output connectors; subject to change by component vendor.
 
Physical/mechanical parameters Shunt Value: 1 mA to 20 A
Weight: 0.7 kg （1.6 lb）
Input Connector: Type-N （female）
Output Connector: Type-N （female）
Shunt Value: 50 A and 100 A
Weight: 3.4 kg （7.5 lb）
Input Connector: Type-LC （female）
Output Connector: Type-N （female）
 
Operating environment Temperature: 13 °C to 33 °C
Calibration temperature （TCal） range:

18 °C to 28 °C
Humidity range for best specification 1,2:
≤ 50 % RH
Altitude: 0 m to 3,000 m

1 Resistance stability is affected by humidity, but changes are reversible.
2 If the shunts are calibrated outside this RH, stability specifications will be met as long as the shunts are stored and used at the same relative humidity ± 10 % RH.
 
Storage and transit environments （for models other than the 1 mA current shunt） Temperature to avoid damage:
-20 °C to 140 °C
Temperature and humidity to maintain performance1:

5 °C to 45 °C; 15 % to 80 % RH
Non-operating altitude:
0 m to 12,000 m

1 Storage at extremes of temperature or humidity will cause a temporary change of shunt resistance by up to ± 20 ppm. When subsequently stored or used within the limits of the operating environment, the shunts will recover to their original resistance value within 30 days.
 

Additional 1 mA current shunt specifications
Output resistance 8 mΩ
 
Maximum safe output current 11 mA （e.g., 1 V output into 90 Ω）
 
Maximum capacitive load 800 pF
 
Output voltage regulation 15 ppm/100 pF
 
Maximum output dc v offset ± 100 μV （typical ± 25 μV）
 
Typical error @ 1 MHz < 2 %
 

Battery specifications
Battery size AAA （44.5 mm x 10.5 mm）
 
Battery technology Nickel-Metal Hydride （NiMH）
 
Number of batteries required 8 （in 2 groups of 4）
 
Nominal battery voltage 1.2 V （4.8 V per group of 4）
 
Typical battery capacity 800 mAh
 
Storage and transit environment to preserve the batteries Less than 90 days: -20 °C to 40 °C
Less than one year: -20 °C to 30 °C
Charging time （from fully discharged）: 100 minutes
 
Maximum operating time between charges Maximum output load （11 mA）:
18 hours
High impedance load: 24 hours
Recommended cooling period: 100 minutes
To prevent loss of battery capacity recharge at least twice per year.