ACM-1A ACPD CRACK GROWTH MONITOR
300 Hz output frequency, normally fixed. Variable frequency models
Built in scan controller, measure multiple locations from one unit.
Built in high precision pre-amplifier circuitry.
Small compact size! Measures only 160 * 160 * 60 (mm)
2 Amps output, normally fixed. Variable current models available.
Two channels as standard, measure active and reference signals.
Wi-Fi and Ethernet communication modules available.
Fixed gain setting at 20,000
Slow crack growth
Stress corrosion testing
Fatigue crack initiation
Designed as a 'Black Box' ACPD crack growth monitor to reduce costs and simplify end user installation, the
ACM-1 is ideally suited to semi-permanent installations for long term crack growth monitoring, for example in
power utility installations and structural applications.
The ACM-1 utilises the alternating current potential drop method (ACPD) which is an established technique
covered by the ASTM 647 standard. The technique involves passing an alternating current through the metal
under test and measuring the resultant voltage drop that is created across the specimen. The presence of a
growing defect will alter this voltage and by suitable calibration, a measure of the defect depth can be