epro CON 011 - Mutual Influences of Two Measuring Chains

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Direction for Use (GB) / Gebrauchsanleitung (D)
Converter CON 011
Direction for use
• the measuring range maximum (= maximum distance) −20V (−4...−20V) resp. –18V (–2...
−18V) for single sided displacements in direction to smaller values (smaller distances)
(Fig 3, A
max
)
• or any other value within the measuring range if different displacements in both directions
are to be measured (unsymmetrical measuring ranges)
Fix the mounting flange in the correct position and secure screws and nuts to prevent them from
getting loose. The sensor must be mounted vertically to the measuring target.
1.3.4 Mutual influences of two measuring chains
If two eddy current measuring chains are mounted close together, it might happen that they
influence each other and generate invalid measuring results. This could e.g. happen with a shaft
vibration measurement by using two PR 6423 sensors, mounted in an 90° angle at a shaft with
≤100mm diameter, in case of measuring shaft displacements with two sensors in tandem
arrangements, with cone or double cone arrangements of two sensors.
In this case the carrier frequency must be slightly shifted at one of the converters by opening link
J1 (e.g. with side−cutting pliers). After this, the measuring chain must be calibrated anew,
refer to section 1.3.5.
1.3.5 Recalibration of the converter ( only necessary in special cases )
The adjustment is made with a micrometer calibration device, refer to Fig 9.
STOP
Before soldering at the converter, switch off the supply power.
!
To change the output voltage range from –2...−18V to –4...−20V, link J2 must
be opened. This action does only change the voltage range without any
influence on linearity or adjustment of the measuring chain.
Opening of link J1 increases the oscillator frequency of the converter by approx. 250 kHz, a new
adjustment of the measuring chain according to the following description is necessary. The
position of the components is shown in Fig 2.
Adjustment sequence for PR 6422...6424 and PR 6426:
Adjustment steps: [...] values are valid for J2 open
1. Desolder resistances R 22 (gain factor, approx. 0...10kΩ) and R 23 (zero point, approx. 10kΩ
...200kΩ) and connect resistance decades to these positions. Set potmeter GAIN to centre
position. Resistance R24 depends on the sensor type:
PR 6422 / 6423 / 6425: 4,02kΩ, PR 6424: 5,62kΩ, PR 6426: 10kΩ.