EP-4 AC Magnetic Field Probe - Magnetic Shield - #2

The A.C. magnetic field evaluator probe may be used with a digital volt meter or oscilloscope to determine A.C. magnetic field sources and inten­sities. It is also used to measure the attenuation of magnetic shields.

The nominal probe output is 60 millivolts per gauss at 60 Hertz. The formula on the probe label gives the individual probe calibration number and the correction for other frequencies. The probe pro­vides for direct measurements in gauss for fre­quencies up to 3 kHz. At higher frequencies ac­curacy is reduced, but the probe remains useful for determining relative values of shielded versus unshielded areas.

NOTE: The connector shown in the photos is no longer available. Probes are supplied with BNC connector. BNC to dual banana adaptor available upon request.

The probe formula is:

60 • E ( pe a k mv) *

Cal. No. • f(Hz)

*Peak voltage as determined with an oscilloscope. If using an instrument that reads rms voltages, multiply the reading by 1.414 before using formula.

The probe is an air core inductor sensitive to mag­netic flux lines crossing the plane identified by the yellow stripe on the housing. By orienting the probe for maximum output, the source of an interference field can be located. For durability, the probe coil and the slotted electric field shield are encapsu­lated in an epoxy housing. The housing is 1³/s" (35 mm) diameter and 2¹/4" (58 mm) long. The cable is shielded to prevent loop current

pickup. The

output connector is standard BNC.

The probes are furnished with either axial or trans-

FIG. A-AXIAL MODEL • ORDER

EP-102A

verse pickup coil positions to facilitate

correct

orientation in restricted areas. Figure "A" shows

v Dana in

that a maximum reading will be obtained with the housing axis aligned with the field. Figure "B"

shows the transverse type which gives a maximum

reading when the field approaches the side of the housing perpendicular to the plane of the yellow

stripe.

A.C. magnetic field evaluator probes are extremely ning interference field intensity.

With this essential

information, the proper gauges

NETIC magnetic shielding alloys can be specified. Magnetic shield designs can be optimized by hand forming prototypes from ma-available in our Lab Kit. Please refer to

t

brochure LK-4.

FIG. B - TRANSVERSE MODEL • ORDER EP-102T

Perfection Mica Co. 740 N. Thomas Drive Bensenville, IL 60106 U.S.A.

Fax 630-766-2813 Phone 630-766-7800

Catalog EP-4D • Copyright 2009, Magnetic Shield Corp., Perfection Mica Co.

Printed in U.S.A.