Fluke 52120A, Руководство пользователя

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Front-Panel Operation
How to Use the Accessory Coils with the Product
2
2-19
4. Connect a second control cable between the Current Amplifier Control Output
connector on the rear panel of one of the 6106As and the Control Input connector on
the rear panel of the second Product.
5. Do step 4 for the second 6106A.
Figure 2-7 shows the connection between a 6105A or 6106A and each Product.
In this setup, the 6105A controls the two 6106As. Each can be set to output a different
phase signal to their related Products. Each Product current output is controlled by the
6105A or 6106A connected to their auxiliary control input.
How to Use the Accessory Coils with the Product
The accessory coils are used in the calibration of current clamps and Rogowski current
coils. An input current of 120 amps into the 25-turn coil results in a magnetic field
equivalent to 3000 A to calibrate clamp meters. An input of 120 amps into the 50-turn
coil results in a magnetic field equivalent to 6000 A in a horseshoe-shaped coil to
calibrate Rogowski current coils. The magnetic field of the coils changes in proportion to
the input current.
Current/Hz Profile
The usable bandwidth of the accessory coils for a given input current is set by the voltage
compliance limit of the current source. The voltage compliance limit is a function of coil
impedance. With a voltage compliance limit of 4.5 volts in the Product, the maximum
impedance that the Product can supply 120 A into is 0.0375
Ω
. The maximum impedance
includes the coil which is mostly inductive and the connections and cables.
Current Cable Connection
Make sure the connection at the coil input terminal posts are tight, so the connection
cables and coil terminal posts do not get too hot. Keep the cable length to a practical
minimum. For minimum loop impedance, put the cables close together and tie them
together at regular intervals.
Current Clamp Calibration
Some current clamps and Rogowski coils are sensitive to their position in a magnetic
field. To do a sensitivity test, move the position of the device to be calibrated in the
accessory coil field and look for changes in the output. Usually a central position gives
the best results.
Built-In Fan
A 12-V dc fan to cool the coil is built-in to the accessory coil. The electrical connection is
a BNC-terminated cable that comes out of the coil base. The Product has a BNC
connecter on the front panel (OPTION POWER OUTLET) that supplies 12 V dc to the
coil fan. If the accessory coils are used away from the Product, 12-V dc power can be
supplied with the 52120A/COIL12V DC Power Supply. The fan must blow air through
the coil.
W
Warning
To prevent fire, personal injury, or damage to equipment, do not
use the accessory coil if the fan is not turned on.