Fluke Calculator 5500A COIL User Manual

Instruction Sheet

Model 5500A/COIL

50-Turn Current Coil

Introduction

The 5500A/COIL is a 50-Turn Current Coil used as a tool for calibrating clamp-type current meters that

operate by two different principles—as current transformers (AC only), and by the Hall Effect (Both AC

and DC). It is impractical to calibrate 1000A rated current clamp meters using a 1000A source. How-

ever, by using the 50 turns of the 5500A/COIL in conjunction with a current source calibrator one can ef-

fectively multiply the current of the current source calibrator by a factor of 50 to support the calibration

and verification of these clamp-type current meters.

PWARNING

UNFUSED. Exceeding current and voltage ratings can cause burn or fire hazard.

Using the Coil

Clamp-type current meters operate as current transformers, with differing degrees of magnetic coupling

between primary and secondary that vary from meter to meter. The position of the clamp meter with re-

spect to the cable also affects the magnetic coupling between primary and secondary of the current trans-

former, which causes variation in reading of

the current meter. This is important to under-

stand in order to make the most accurate and

repeatable measurements. The base of the

5500A/COIL was designed so the current

clamp can be centered carefully on the coil,

minimizing operator error for best repeatabil-

ity. Calibration accuracy to specifications is

guaranteed only when proper clamp alignment

is made. The clamp current meter should be

centered as much as possible on the base dur-

ing calibration and verification. If the clamp-

type current meter has alignment marks, the

alignment marks should align the clamp with

the center bundled wire of the 50-Turn

5500A/COIL. (See Figure 1).

Figure 1. Positioning the Clamp

PN 600616 August 1995 Rev.7, 7/08