12. Calibration
The BALTO Calibration Tool is available as a separate product and allows the operator to re-calibrate the device. The
tool consists of:
Calibration sensor (LEM 20,000 A / 10 VDC).
Calibration sensor power supply
(230 VAC / 50 Hz or 120 VAC / 60 Hz to ±15 VDC).
Set of connecting cables.
12.1 Preparations
NOTE :
It is recommended to charge the BALTO System during 48 hours before starting the calibration
procedure.
The BALTO System must be connected to a circuit to perform re-calibration. It is recommended to use a High-speed
DC Circuit Breaker with a sufficiently high trip level for this.
To measure the flowing current, the calibration sensor (LEM 20,000 A / 10 VDC) must be inserted into the circuit by
running the Power Flex-cables through it, as shown below:
Fig 48:
Sensor for calibration.
Ensure the sensor’s arrow indicator matches the direction of current (pointing from positive to negative).
Connect the measurement cables to the system µΩ inputs of the Control Panel.
12.1.1 Calibration sets
System calibration is performed separately for each configuration of the DC Current Generators. Each calibration is
known as a ‘Calibration Set’.
A configuration is defined as the number of connected DC Current Generators. There is a calibration set for one
connected DC Current Generator, a set for two connected DC Current Generators, and so on. A BALTO Modular
System contains up to 5 calibration sets. The BALTO COMPACT 4000 has only 1 calibration set.
NOTE :
It is important to always use the same DC Current Generators - and in the same order - used during
calibration for each configuration.
When re-calibrating, it is possible to only re-calibrate a single set. Though, re-calibrating all sets is advised to obtain a
complete system re-calibration.
For performing a complete system re-calibration, the following procedure is advised:
Disconnect all but one DC Current Generator.
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Calibration
