TARGA III External DAQ Usage

Capacitive TechNote LT03-0026

Summary

Details the use of the National-Instruments-ready DAQ connector on the rear panel of the TARGA III for use with external data acquisition operations.

External Data Acquisition

The TARGA III is configured for easy connection to National Instruments™ data acquisition systems. The rear panel DAQ connector is a high-density 68‑pin connector which connects directly to National Instruments™ E-series cards and USB-6251 data acquisition modules. The specific signals and pinout of the DAQ connector are detailed at the end of this TechNote.

DAQ Connector Pinout

DAQ Connector as viewed on the rear panel. pins

DAQ Connector Signal Descriptions

Pin	Signal	NI Input	Description
33	Analog Output	ACH1 (+ACH1)	Analog output from BNC on display module
66	Ground	ACH9 (–ACH1)	Connected to ground
57	RPM Out	ACH7 (+ACH7)	Square wave, 1/2 Index input frequency, 0 - 3.3 VDC
23	Ground	ACH15 (–ACH7)	Connected to ground
51	Output Bit 0	DIO5	TTL, Least Significant Digit (See table below)
16	Output Bit 1	DIO6	TTL (See table below)
48	Output Bit 2	DIO7	TTL, Most Significant Digit (See table below)

Output Bits

This 3-bit code divides the output voltage range into six divisions according to the following table:

Bit 2	Bit 1	Bit 0	Output Voltage
0	0	0	Vout < –5V (out of range)
0	0	1	–5V < Vout < –2.5V
0	1	0	–2.5V < Vout < 0V
0	1	1	0V < Vout < +2.5V
1	0	0	+2.5V < Vout < +5V
1	0	1	+5V < Vout (out of range)

Index Input

The index connector on the front of the TARGA III is configured for use with the Lion Precision optical RPM sensor (P015-3375). This fiber-optic sensor uses a black mark on the rotating gage pin to generate a square wave (RPM Out) which is half the frequency of the spindle's revolutions per second. Contact a sales engineer or a Lion Precision representative for details.