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.

The board features:

• 16 high impedance isolated input channels (differential impedance of 20 MOhms and single-ended impedance of 10 MOhms per channel),

• a maximum voltage of up to 400V, configurable by jumpers,

• selectable voltage, current or resistive sensor mode per channel.

Board Layout 

Open

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.

Open

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..

B Voltage Level Selection

• Low voltage or current mode: the jumpers must be on pins 3/4 and 15/16. Voltage range selectors must be in OFF positions.

• High voltage mode: the jumpers must be on pins 1/2 and 17/18. Voltage range selectors (SW2 and SW3) must be set according to the desired voltage. (see list C below).

C Voltage Range Selection

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

• To obtain 100V, the SW2 screw must be in the +/-100V position and SW3 in the OFF position

• To obtain 200V the SW2 screw must be in the +/-200Vposition and SW3 in the OFF position

• To obtain 400V, the SW2 screw must be in the OFF position and SW3 in the +/-400V position

• To obtain 600V the SW2 screw must be in the OFF position and SW3 in the +/-600V position

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.

Optional Mezzanine Mode Selection

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).

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).

Resistive Sensor Mode Diagram

The following diagram applies only when the optional Resistive 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 Resistive 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.

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.

DB37F Connector Pins Assignment

Specifications