| CMSS 68 eddy current probe system |
| Unless otherwise noted, the following specifications apply to a complete CMSS 68 eddy current probe system, at 23 °C (73 °F), with a –24 V DC supply and target of AISI 4140 steel, comprising of |
- CMSS 68:Eddy current probe
- CMSS 958: Extension cable
- CMSS 668 or CMSS 668P: Driver
|
| Note |
These specifications may vary with different options and systems. |
| Usable range |
2,3 mm (0,2 to 2,5 mm); 90 mils (10 to 100 mils) |
| Sensitivity |
7,87 mV/µm (200 mV/mil) |
| Linearity |
±25,4 µm (1 mil) of best straight line over
2,3 mm (90 mil) range |
| Frequency range |
DC to 10 kHz (600 000 CPM), down maximum
of 3 dB at 10 kHz |
| Driver signal output |
Impedance: Minimum calibrated load resistance of 3 kO; output –
is protected against miswiring
Voltage: Nominal 7,87 mV/µm – (200 mV/mil) corresponding to
–18 V DC at 2,3mm (90 mils) with –24 V DC supply |
| Power supply requirements |
15 mA from –24 to –30 V DC |
| Interchangeability |
Probes, extension cables and drivers are compliant to API 670 –
requirement and may be interchanged with 5% or less
performance change without recalibration
All units factory calibrated at 23 °C – (73 °F)
Trim calibration adjustment on driver provides duplication of –
characteristics after replacement of any component |
| CMSS 68 probe |
| Operating temperature range |
–35 to +175 °C (–30 to +350 °F)
(Note: Ex i regulations restrict upper limit to 100 °C (210 °F)) |
| Differential pressure |
To 4 bar (60 PSI) |
| Materials |
Case: Grade 300 stainless steel –
Tip material: Ryton –
Connectors: Nickel plated stainless steel; weatherproof, sealable –
Cable: Coaxial with fluorine based polymer insulation; high –
tensile and flexible strength |
| Mounting |
Recommend minimum clearance of 1/2 probe tip
diameter around the probe tip to maintain factory calibration |
| CMSS 958 extension cable |
The temperature ranges, connectors and cable are the same as the
CMSS 68 eddy current probe. |
| Operating temperature range |
0 to 65 °C (30 to 150 °F) |
| Connections (Power, Signal, GND) |
Five terminal removable and reversible compression terminal –
block accepting up to 2 mm 2 (14 AWG) wire
Three connections necessary per block (–24 V DC, GND, Signal) –
The CMSS 668P has a permanent fixed connector with the –
same connection characteristics |
| Mounting |
C-DIN rail mount that bolts onto the driver enclosure or
the standard four 4,8 mm (0.19 in. or #10) clearance holes in a
square on 63,5 mm (2.5 in.) centers |
The following performance characteristics apply for the CMSS 68
eddy current probe system in addition to quoted nominal
specifications |
| Extended temperatures |
With 1 m (3.3 ft.) probe and 4 m (13.1 ft.)
extension cable operating in a range of –35 to +120 °C
(–30 to +250 °F), and driver in the range of 0 to 65 °C
(30 to 150 °F) |
| Sensitivity |
±10% of 7,87 mV/µm (200 mV/mil) |
| Linearity |
±25,4 µm (1 mil) of best straight line over
2,3 mm (90 mil) range |
| Minimum target size |
Flat surface: 16 mm – (0.63 in.)
Shaft diameter: 24 mm – (0.93 in.) |