Eurotherm 590SP, Руководство по эксплуатации продукта

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Appendix A Technical Description
A
590SP Digital Product Manual
App. A - 11
FEEDBACK OPTION CARDS
Both the standard and DRV models of the 590SP Digital drive are preconfigured to run in armature voltage feedback
control, which requires no feedback device. Accordingly, each is shipped without a feedback option card. Order one
of the four cards described below when using an analog tachometer generator, Microtach or wired-ended encoder for
speed feedback.
Switchable Tachometer Feedback card (AH385870U001)
The switchable tachometer generator feedback board supports AC and DC analog tachometer generators. It can be
used with analog tachometer generators with a feedback voltage range of 10 to 199 volts at full speed.
Features
• Simplified calibration using switches to scale the feedback voltage.
• 0.1% steady state accuracy.
Specifications
DC power supply loading 50 mA
Tachometer generator supply range 10 to 199 volts AC/DC
Terminal Wire Size 22 to 14 AWG
(0.5 to 1.5 mm
2
)
Terminal Tightening Torque 5.3 lb-in (0.6 Nm)
Recommended Spare Parts
Keep only one tachometer generator feedback card as a spare.
Installation Information
Figure A.3 shows a close up of the card. Terminal connections are also shown.
NOTE. Be certain to wire the tachometer generator leads to the feedback card with shielded cable and
to ground the shield at one end only, to avoid creating ground loops.
Calibration
1. Set the tachometer generator type by setting SW4 up for AC tachometer generators, or down for DC tachom-
eter generators.
2. Set the ones and tens switches to the calibration volts by sliding the appropriate 10-position switch to the
correct value. To add one hundred volts, switch the two-position switch (SW3) down. This coarsely scales the
analog tachometer generator signal.
In general, the voltage output of an analog AC or DC tachometer generator is a function of speed or is rated in
volts per 1000 rpms so that:
( )
( )
SPEED FEEDBACK VOLTAGE volts MOTOR SPEED RPM T
Max Max
= ×
This rating should be on the nameplate of the tachometer generator. Fine tuning is performed within the
software (refer to the Calibrate Speed Feedback section in Chapter 4).
If the full speed feedback voltage exceeds 200 VDC, use an external resistive scaling network to drop the
feedback voltage to within this range.
3. For AC tachometer generators, the switch settings will be about 1.3 times greater than the voltage measured at
the input terminals G1 and G2 due to the rectifier offset.
Figure A.3 - Switchable Analog
Tachometer Feedback Card