The OP7818, designed for use with the OP7000 chassis, features 16 analog input channels. It is perfectly suited to interface simulator signals to real-life environment signals, providing electrical isolation.


This board is not supported with the OP7000V2 chassis.



The board features:

Board Layout 

P7818 board

Configuration

Jumper and Switch Positions

Each channel has a series of jumpers and switches, seen in the figure below, that enables onboard mode selection (voltage or current) and, subsequently, voltage range configurations. Each element enables a function that allows setting a very precise configuration for the OP7818 board.


OP7818 jumpers

A Mode Selection

Switch (SW4) lets you place the board in either voltage or current mode. Slide the switch to the right (towards U) to set the channel to Voltage mode or to the left (toward I) to set the channel to Current mode..

Mode Selection

B Voltage Level Selection

Voltage Level Selection

C Voltage Range Selection

To obtain +/- 20V, both the SW3 and SW2 screws must be in the OFF position.

Voltage Range Selection

Optional Mezzanine Board

When working in low voltage mode, the Ain Resistive Sensor mezzanine can be used to take temperature measurements using either a thermistor or a resistive sensor.

Resistive Sensor adaptor mezzanine

Optional Mezzanine Mode Selection

ModeScrew PositionResistor Description
+/-18V
3VREF
OffIf the board is using the resistive sensor
module, it can acquire analog signals up to +/-3V
which are then amplified to +/-18V

RTD+/-100Vpull-up=2.05KOhm

Thermistor+/-200Vpull-up=3.32Kohm
one pull-down=47.5KOhm

Typical application diagrams

Voltage Mode Diagram

The following diagram applies when the board is set to operate in Voltage mode: jumpers are on pins 3/4 and 15/16 (J4) and SW2 and SW3 screws are in off position and switch SW4 is in Voltage mode (position U).

Voltage mode diagram


Current Mode Diagram

The following diagram applies when the board is set to operate in Voltage mode: jumpers are on pins 3/4 and 15/16 (J4) and SW2 and SW3 screws are in off position and switch SW4 is in Current mode (position I).

Current mode diagram

Resistive Sensor Mode Diagram

The following diagram applies only when the optional Resisitve Sensor mezzanine board is in place.

Using the screw (SW1) on the mezzanine board, the OP7818 can be set to operate with a thermistor or resistive sensor. Note that with the mezzanine board in place, there can be no jumpers on pins for jumper array (J4) and SW2 and SW3 screws must be in the off position and switch SW4 is in Current mode (position I).

In Resisitive sensor mode, the screw must be turned to the left, to RTD.

In Thermistor mode, the screw must be turned to the right, to THER.

Thermistor mode diagram

Installation

The OP7818 analog input signal conditioning module must be inserted at the back of the OP7000 simulator in the odd-numbered slot corresponding to the front slot where the OP7220 is installed. See page OP7000V2: Adding or Replacing Boards for more details (the same applied for the OP7000 chassis).

Make sure that the board is properly aligned using the guide tracks before pressing it into place.

Face Plate

The faceplate provides a DB37F connector (see “connector pin assignments” for details) and a series of status LEDs.

Each LED represents a channel, as shown in the table below. If the LED is green, it indicates that the channel is in Voltage mode. If the LED is orange, the channel is in Current mode.


Back 6U board LEDs

DB37F Connector Pins Assignment

DB37

Connector

Channel

DB37

Connector

Channel


1

+IN00

20

-IN00

Pin Assignments

2

+IN01

21

-IN01

3

+IN02

22

-IN02

4

+IN03

23

-IN03

5

+IN04

24

-IN04

6

+IN05

25

-IN05

7

+IN06

26

-IN06

8

+IN07

27

-IN07

9

+IN08

28

-IN08

10

+IN09

29

-IN09

11

+IN10

30

-IN10

12

+IN11

31

-IN11

13

+IN12

32

-IN12

14

+IN13

33

-IN13

15

+IN14

34

-IN14

16

+IN15

35

-IN15

17


36


18


37


19

Specifications

Product name

OP7818

Part number

126-0391

Product type

OP7000 back 16 Ain

Number of channels

16

Input modes

Voltage,  current or resistive sensor

Isolation

Provided by OP7000

Maximum Current

±25 mA

Maximum voltage

±20 V

Dimensions

18.8 x 16.4 cm (7.4 in x 6.46 in)

I/O connector

DB37F

Operating temperature

10 to 40 ºC (50 to 104ºF)

Storage temperature

-55 to 85ºC (-67 to 185ºF)

Relative humidity

10 to 90%, non condensing

Maximum altitude

2,000 m (6562 ft.)