Laser LS8000-3 manual QualityFactor = Voltage ⋅15, Measurement Synchronization Input Pins

LaserSpeed 8000-3 Instruction Handbook

Interfacing with the LS8000-3

Voltage = Measured Analog Output Voltage

Note that when the output voltage is at either limit, the exact speed cannot be determined. If the exact speed is always required, be sure to set the Full Scale Velocity setting to a value higher than what can normally be encountered.

The analog port can also be configured to output the QF on a 0–1 V scale by setting the Full Scale Velocity to zero using a serial command or LaserTrak software. In this case, the analog output reads 0V when the QF is 0 and 1V when the QF is 15.

When the Analog Output is configured to output Quality Factor, the Quality Factor can be calculated with the following equation:

QualityFactor = Voltage ⋅15

Analog Output / Volts

Analog Output vs Quality Factor

1

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

00	2	4	6	8	10	12	14	16
				Quality Factor

When connecting to the Analog Output Voltage, the Analog Output Voltage and Analog Output Ground should be on a separate twisted pair inside of a shielded cable. Connect a 0.1∝F capacitor across the load end of the cable (the end opposite the gauge) to reduce noise caused by other signals in the cable. See the following wiring example:

Gauge DB9

			Analog Output Cable
		Analog Output+ (Pin 6)
			Shielded, Twisted Pair
	Analog Output Ground (Pin 7)
Terminate Shield/Drain Wire to backshell of DB9 connector

Cable Jacket

Cable Shield

0.1∝F

Terminate Shield/Drain Wire to

Chassis Ground

1000Ω minimum

Analog Output Wiring Example

Measurement Synchronization Input (Pins 8-9)

In many AGC applications, particularly mass flow control, it is desirable to synchronize the sampling periods of all gauges in the system. This is done by connecting an LS8000-3 I/O Module to each LS8000-3 in the system (for

Part No. 93463 / Drawing No. 0921-01561 Page 59 of 221 Revision A (Sep 2007)