Flintec LDU 69.1 - Manual (Page 6)

LDU 69.1 Technisches Handbuch, Rev. 12 January 2011 Page 6 of 28
3. Introduction and Specifications
The model LDU 69.1 is a very precise digital amplifier for weighing and force measurements with strain gauge
(SG) sensors. The LDU 69.1 can be used in legal for trade as well as for industrial applications. The device
features full multi-drop communications capability and can be programmed via a straightforward ASCII
command set.
The LDU XX.X series and the amplifier DAS 72.1 with on-board digital display, use the same command set.You
can connect up to 32 SG amplifiers of either the LDU XX.X series or DAS 72.1 type onto a single RS 485 bus.
The LDU 69.1 with its very precision A to D converter and an internal sample rate of up to 172 measurement
values per second, is particularly suitable for static or dynamic measurements and control purposes. In multi-
channel applications, e.g. test stands (reference and test sample), the measurements have to be synchronized.
For this purpose there is a 8 channel adaptor board UA103 which is suitable for the synchrone operation of up
to 8 LDU 69.1 amplifiers.
LDU 69.1 Specifications
Accuracy class III
Test certificate according OIML R76 10 000 intervals, n x 10 000 intervals (n = 2 or 3)
Linearity < 0.001 % FS
Excitation 5 V AC (appr. 86 Hz), load cells > 250 Ohm; 6 wire technique
Analogue input range
±11 mV (bipolar; for weighing applications, force and torque
measurements)
Minimum input sensitivity 0.02 μV / d
Certified accuracy according OIML R76 0.1 μV / e (legal for trade)
Resolution > ± 1 000 000 counts (input); ± 1 000 000 counts (output)
Conversion rate 172 values/second internal, up to 172 values/second external
Digital filter
IIR filter 0.2 to 3 Hz; in 6 steps adjustable (0,2; 0,5; 1; 1,5; 2; 3)
Bessel, Gauss or Butterworth characteristics
Calibration By software via ASCII commands, sehr einfach durchführbar
Communication interface
RS485 oder RS422; Voll-Duplex oder Halb-Duplex;
9600 ... 115200 Baud; busfähig bis zu 32 Einheiten
Standard weighing functions Gross, tare, net, zero, etc.
Temperature effect on zero Typical 1 ppm/°K; max. < 2 ppm/°K
Temperature effect on span Typical 1 ppm/°K; max. < 2 ppm/°K
Temperature range –15 °C to +50 °C (operation); –20 °C to +60 °C (storage)
Enclosure
Tinned steel enclosure, IP40 protection,
special IP65 housing on request
Dimensions and weight
82 x 31 x 6 mm, weighs approx. 30 g;
with adaptor board 99 x 41 x 12 mm, approx. 50 g
Power supply 12 ... 24 V DC ±10 %, < 60 mA, not galvanically isolated
Available accesoires
Adaptor board UA73.2 (RS485 / RS422) or
Adaptor board UA77.1 (inkl. converter RS422/RS232)
Adaptor board UA103.1 (RS485, for 8 pcs. LDU)
EMC OIML R-76:2006 and DIN EN 45 501:1992/AC1993