IS220PAICH1B - IO PACK ANALOG IN/OUT BASIC

The IS220PAICH1B is a GE Analog I/O pack from the Mark VIe series. The PAIC pack serves as the electrical interface between one or two I/O Ethernet networks and an analog input terminal board. The pack includes a processor board shared by all Mark VIe distributed I/O packs and an acquisition board dedicated to the analog input function.

IS220PAICH1B Functional Description

• The pack can handle up to ten analog inputs, the first eight of which can be configured as 5 V or 10 V inputs or 0-20 mA current loop inputs. The last two inputs can be set to 1 mA or 0-20 mA current inputs.
• The load terminal resistors for the current loop inputs are located on the terminal board, and the PAIC senses voltage across these resistors. The PAICH1 also has two 0-20 mA current loop outputs. The PAICH2 includes additional hardware to support 0-200 mA current on the first output.
• The pack is powered by a three-pin power input and two RJ45 Ethernet connectors. Output is via a DC-37 pin connector that is directly connected to the associated terminal board connector. LED indicator lights provide visual diagnostics.

Processor features

• The processor board is linked to an acquisition board dedicated to the function of the I/O pack or module. When input power is applied, the soft-start circuit increases the voltage available on the processor board. The local power supplies are turned on in sequence, and the processor reset is disabled.
• After finishing self-test routines, the processor loads application code specific to the I/O pack or module type from flash memory. The application code reads board ID information to ensure that the application code, acquisition board, and terminal board are all correctly matched.

Auto-Reconfiguration

• The Auto-Reconfiguration feature allows the operator to replace I/O packs without having to manually reconfigure each pack or module.
• When the controller detects an I/O pack booting with a different configuration and the Auto-Reconfiguration feature is enabled, a reconfiguration file is automatically downloaded from the controller to the I/O pack. The bootload, baseload, firmware, and parameters are all reconfigured.
• Unless it already has the latest version, each I/O pack is updated with the current configuration that matches the configuration used by the controller.

Analog Input Hardware

• For all ten input channels, the PAIC accepts input voltage signals from the terminal board. An analog multiplexer block, several gain and scaling options, and a 16-bit analog-to-digital converter comprise the analog input section (DAC).
• Depending on the input configuration, the inputs can be configured as 5 V or 10 V scale signals. When configured for current inputs, the terminal board includes a 250 burden resistor that produces a 5 V signal at 20 mA.

Analog Output Hardware

• The PAIC has two 0-20 mA analog outputs that can operate at 18 V compliance in simplex or TMR mode. A 14-bit DAC sends a current reference to the PAIC's current regulator loop, which detects current in both the PAIC pack and the terminal board.
• Each analog output circuit also includes a normally open mechanical relay for enabling or disabling output operation. The relay is used in a TMR system to remove a failed output, allowing the remaining two PAICs to create the correct output without interference from the failed circuit.
• When the suicide relay is deactivated, the output opens through the relay, short-circuiting the PAIC's analog output from the terminal board's customer load.