AMPETRONIC FSM IEC60118-4 FIELD STRENGTH METER

Condition: Used

The Ampetronic FSM IEC60118-4 Field Strength Meter is a compact, handheld instrument for assessing the performance of induction loop systems. Supplied as pictured with no additional accessories included.

What's included:
• Ampetronic FSM Field Strength Meter unit only

Note: No additional accessories are included with this unit.

The Ampetronic FSM is a cost-effective, ergonomically designed handheld instrument for measuring, setting up and commissioning any audio induction loop system to the requirements of IEC60118-4. It is suitable for use by loop system installers, facilities managers and engineers for initial commissioning, routine monitoring, and compliance verification.

The FSM features three calibrated operational modes:

1. Background Noise Mode — Determines the level of background magnetic flux present at the installation location using an A-weighted filter. Scale: -12dB to -42dB. Can also be used to assess overspill outside the loop coverage area.

2. Field Strength Mode — Broadband measurement for assessing system field strength. Suitable for use with a test signal source or real programme signals.

3. Frequency Response Mode — Uses third-octave filters at 100Hz, 1kHz and 5kHz to measure frequency response as stipulated by IEC60118-4. Used to confirm adequate power at high frequencies and assess frequency-dependent loss due to metal structures. For use with pink noise signal only.

The meter also functions as a loop listener via its headphone output, allowing the user to audibly monitor the loop signal.

Key Features:
• Simple assessment of any induction loop system to IEC60118-4
• Three modes: A-weighted background noise, broadband field strength, frequency response
• True RMS detection, 125ms integration time
• Calibrated reference level: 400mA/m = 0dB
• Wide viewing angle LED display with colour-coded LEDs
• Resolution: 1dB
• Headphone output with volume control (3.5mm jack, min. 32 ohms/channel)
• Class 2, Type 2 meter per IEC60118-4 and IEC61672-1
• Gain stability: better than 0.5dB across all conditions
• Compatible with any induction loop system, regardless of manufacturer or type
• Annual recalibration recommended

Technical Specifications:
Measurement Type: True RMS, 125ms integration
Reference Level: 400mA/m (0dB) in Field Strength mode
Field Strength Mode Range: -22dB to +8dB
Background Noise Mode Range: -12dB to -42dB
Frequency Response (Field Strength): 50Hz to 8kHz ±0.25dB; 30Hz to 10kHz -3dB
Frequency Response Mode Filters: Third-octave at 100Hz, 1kHz and 5kHz
Display Resolution: 1dB
Headphone Output: 3.5mm jack socket
Minimum Headphone Impedance: 32 ohms per channel
Coil Orientation: Vertical when instrument held upright
Power Supply: 2 x AA alkaline batteries
Battery Life: Up to 100 hours (use-pattern dependent)
Battery Monitor: LED indicator
Dimensions (H x W x D): 84 x 140 x 27 mm
Weight: 150g (excluding batteries)
Meter Classification: Class 2, Type 2 per IEC60118-4 / IEC61672-1

Ampetronic FSM Field Strength Meter — Official Datasheet (PDF): Download PDF

Ampetronic FSM Field Strength Meter — Full Handbook / User Manual (PDF): Download PDF

Ampetronic FSM Field Strength Meter — Quick Start Guide (PDF): Download PDF

Ampetronic FSM Datasheet — Canford Audio hosted version (PDF): Download PDF