Thermo Scientific 5028i Instruction Manual page 229

Analog Current Outputs
Analog Voltage Inputs
Digital Relay Outputs
Digital Inputs
Thermo Fisher Scientific
The optional I/O expansion board includes six isolated current outputs.
These are firmware configured for any one of the following ranges, while
(Optional)
maintaining a minimum resolution of 11 bits:
0-20 mA
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4-20 mA
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The user can calibrate each analog output zero and span point through
the firmware. At least 5% of full-scale over and under range are also
supported, but may be overridden in the firmware, if required.
The analog outputs may be assigned to any measurement or diagnostic
channel with a user-defined range in the units of the selected parameter.
The current outputs are independent of the voltage outputs. The current
outputs are isolated from the instrument power and ground, but they
share a common return line (Isolated GND).
The optional I/O expansion board includes eight analog voltage
inputs. These inputs are used to gather measurement data from third-
(Optional)
party devices such as meteorological equipment. The user may assign a
label, unit, and a conversion table (2 to 10 points). Each point in the
conversion table consists of an analog input voltage value (0-10.5 V)
and a corresponding user-defined reading value. Only two points are
necessary for linear inputs, however, a larger number of points may
be used to approximate non-linear inputs. All voltage inputs have a
resolution of 12 bits over the range of 0 to 10 volts.
The instrument includes one power fail relay on the motherboard and
ten digital output relays on the digital output board. These are reed
relays rated for at least 500 mA @ 200 VDC.
The power fail relay is Form C (both normally opened and normally
closed contacts). All other relays are Form A (normally opened
contacts) and are used to provide alarm status and mode information
from the analyzer, as well as remote control to other devices, such as
for controlling valves during calibration. The user may select what
information is sent out from each relay and whether the active state is
opened or closed.
Sixteen digital inputs are available, which may be programmed to signal
instrument modes and special conditions including:
Filter tape change
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Turn pump off
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Turn pump on
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Analog outputs to zero
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System Description
I/O Components
Model 5028i Instruction Manual 8-9