Digital Output Board; I/O Expansion Board (Optional); Front Panel Connector Board; I/O Components - Thermo Scientific 146i Instruction Manual

Photometer Lamp Power Supply

Digital Output Board

I/O Expansion Board
(Optional)
Front Panel Connector

I/O Components

Thermo Fisher Scientific
The photometer lamp power supply is similar to the ozonator power supply
except for the operating temperature set point and the value of the resistor
in series with the output. The photometer is always "on" when the
operating temperature is reached. Software on/off control is not required.
The digital output board connects to the motherboard and provides
solenoid driver outputs and relay contact outputs to a connector located on
the rear panel of the instrument. Ten relay contacts normally open (with
power off ) are provided which are electrically isolated from each other.
Eight solenoid driver outputs (open collector) are provided along with a
corresponding +24VDC supply pin on the connector.
The I/O expansion board connects to the motherboard and adds the
capability to input external analog voltage inputs and to output analog
currents via a connector located on the rear panel of the instrument. It
contains local power supplies, a DC/DC isolator supply, a sub-processor
and analog circuits. Eight analog voltage inputs are provided with an input
voltage range of 0V to 10VDC. Six current outputs are provided with a
normal operating range of 0 to 20 mA.
The front panel connector board interfaces between the motherboard and
the front panel mounted function key panel and Graphics display. It serves
Board
as central location to tie the three connectors required for the function key
panel, the graphics display control lines, and the graphics display backlight
to a single ribbon cable extending back to the motherboard. This board also
includes signal buffers for the graphics display control signals and a high
voltage power supply for the graphics display backlight.
External I/O is driven from a generic bus that is capable of controlling the
following devices:
• Analog output (voltage and current)
• Analog input (voltage)
• Digital output (TTL levels)
• Digital input (TTL levels)
Note The instrument has spare solenoid valve drivers and I/O support for
future expansion.
System Description
I/O Components
Model 146i Instruction Manual 8-11