Differential Channels,

TB-100 Notes (Apply to the preceding table.)

Note 1: Digital Common Pins on the SCSI III connector are: 35, 36, and 40.

Note 2: Analog Common Pins on the SCSI III connector are: 24, 27, 29, 32, 59, 64, and 67.

Note 3: References are not provided for DaqBoard/500 Series devices. For this reason POSREF and NEGREF are tied to the Analog Return signals. POSREF connects to ARET1 (Pin 20 on the DaqBoard) and NEGREF connects to ARET0 (Pin 54 on the DaqBoard).

Note 4: In regard to DaqBoard/500 and DaqBoard/505: TB-100 connectors labeled “XAPCR” and “CNT0” are both used for ADCLKIN (ADC Clock) and therefore cannot be used at the same time. The XAPCR connector is assigned to SCSI-68 connector pin 2. The TB-100 connector labeled “CNT0” [used for ADCLKIN] is assigned to SCSI-68 connector pin 5. Note that DaqBoard/500 Series devices have only one counter implemented, i.e., Counter 1. Counter 0 is not implemented.

Note 5: In regard to DaqBoard/500 and DaqBoard/505: TB-100 connectors labeled “CNT1” and “XDPCR” are the same dual-function signal (DACKLIN/CNTR1) and therefore cannot be independently driven. CNT1 is assigned to SCSI-68 connector pin 39. XDPCR is assigned to SCSI-68 connector pin 1.

Note 6: The following table provides screw terminal reference for connecting analog channels differentially, as opposed to single-ended.

Differential Channels,

Screw Terminal Reference

 

HI (+)

LO (-)

Ch 0

ACH0

ACH1

Ch 1

ACH2

ACH3

Ch 2

ACH4

ACH5

Ch 3

ACH6

ACH7

Ch 4

ACH8

ACH9

Ch 5

ACH10

ACH11

Ch 6

ACH12

ACH13

Ch 7

ACH14

ACH15

External Connections

WARNING

Always turn the computer power OFF and unplug it before connecting or discon- necting a screw terminal panel or a cable to the PCI card. Failure to do so could result in electric shock, or equipment damage.

The DaqBoard/500 Series boards bring out +5 V to the main I/O connector [J1]. This power line is fused to protect the boards. Connecting or disconnecting cables or screw terminal panels (as well as any user connections to the power line) may blow a fuse, or worse, cause damage to the board. If you are getting incorrect data readings check that the fuse is not blown.

The power line fuse for the +5V to J1 is designated as F3. It is a “Pico Fuse” with a 1.0A, 125V rating.

Connecting User Wiring

Incorrect connection of user wiring is one of the most common problems experienced by users of data acquisition boards. To ensure proper results, you must first determine what type of signal source you are measuring (Ground Referenced Source or Floating Source), and then choose the appropriate input configuration on your data acquisition board (Differential or Single-Ended).

DaqBoard/500 Series User’s Manual

887293

Connections & Pinouts 2-7

Page 23
Image 23
Omega OMB-DAQBOARD-500 External Connections, Connecting User Wiring, Differential Channels Screw Terminal Reference, Hi +