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QE-1008_Instruction Manual_02-2014_ENG
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4. Measuring of load distribution
(= load on each single tie bar)
4.1 Connect the sensors with the ‚Y’-cables to the digital monitor DU-4/D. The tie bar cable 1 should be connected to input 1
etc., switch on the monitor and push ‘RESET’.
4.2 Open and close the machine 2...4 times and press ‘RESET’ between each cycle. The effective, precise measurement can
take place as soon as approx. 1...3 digits offset remain.
The magnet sensors have now settled and are ready for measurements.
4.3 The displayed values are bending compensated, because the measuring values of the two opposite sensors are averaged
at the input.
The displayed microstrain (με) values are the tie bar elongation. Example:
Display 355 = 0.355mm tie bar elongation per meter of tie bar
With this value, the clamping force can be calculated.
The new DU-4DU digital monitor calculates by push-button directly kN or tons.
Y connecting cables
Digital Monitor DU-4DU
GND-Plug
USB-OUT (Optional)
8 extensometers
5. Measuring the tie bar bending for early tie bar fraction diagnosis
With this sensors, the bending of two tie bars can be measured simultaneously, without additional equipmant necessary.
Procedure:
5.1 Place the 1. sensor onto the tie bar (45° angle)
5.2 Connect to the same Y-cable a 2nd sensor, don’t place it onto the tie bar, leave it open.
Connect the Y-cable to the sensor-input one of the DU-4D monitor
5.3 Set the 3rd sensor (180° opposite) and connect it to a 2nd Y-cable
5.4 Connect to the 2nd Y-cable also a QE-1008 sensor, but leave it open and do not place it onto the tie bar
5.5 Connect the 2nd Y-cable on sensor-input two of the monitor
5.6 Proceed now as with standard measurement: display 1 shows now the outer and
display 2 the inner elongation
5.7 A 2nd tie bar can be displayed at the same time on display 3 and 4
The elongation shown is a superposition of load and bending. Very high differences
of both values (e.g. <250μe versus >700μe) can be an indication that the tie bar has
started cracking.
Theoretical display on how to measure the tie bar
bending: one sensor has no load. Make sure that this
open sensor is not exposed to temperature variations.
