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Inputs / outputs
Related Topics
• Configuring option module analog inputs using ION Setup
• Configuring option module analog outputs using ION Setup
• Configuring option module digital inputs using ION Setup
• Configuring option module digital outputs using ION Setup
Analog inputs
Analog input applications
You can use an analog input to monitor an analog signal, for example a flowmeter,
to monitor how much water flows through a pipe.
For analog input operation, your meter takes an analog input signal and provides
the resulting scaled value.
Your meter’s analog I/O option modules can measure either low voltage or current
using standard analog transducers such as 4 - 20 mA current transducers.
Related Topics
• Option modules
Analog input voltage and current mode
You can set the analog input’s mode for voltage or current sensing.
In current mode, the analog inputs have a low input resistance while the meter is
powered on, and a high input resistance when the meter is powered off. In voltage
mode, the analog inputs have a high input resistance regardless of whether the
meter is powered or not.
NOTE: When unpowered, your meter’s analog inputs act like they are in
voltage mode (high input resistance).
When connected to a current output transducer, this high resistance can create a
high voltage. Standard (i.e., 4 to 20 mA) current transducers have open circuit
protection and are able to handle a high input resistance; however, if non-standard
transducers are used high voltages may be generated. Your meter’s analog input
has circuitry to limit this voltage, but it may not be sufficient with a very high-power
current source.
NOTICE
EQUIPMENT DAMAGE
Failure to follow these instructions will result in equipment damage.
• Ensure the analog input is configured for the correct voltage or current mode
before connecting or activating the current transducer.
• Do not exceed the device’s ratings for maximum limits.
Related Topics
• Option modules
Analog input behavior
Analog inputs may show a value below zero scale if an open circuit is detected on
the input port.
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