Large number of batteries
One Nuclear Power Plant can have as many as 100 batteries of various sizes.
Some of them being of extreme importance for the safety of the Plant in case
of an emergency situation. A large battery can comprise 200 cells that are
connected in series.
Safe Battery Monitoring
A Battery Monitoring System can greatly increase the reliability of the batteries.
However, the system must be selected with care since a poorly
designed battery monitoring system will have the opposite effect.
Batscan = Safety
Batscan is jointly developed by TechTrade, Sweden and
Bell Labs, USA. The system was designed for maximum safety and reliability
without compromising performance and user friendliness. Batscan is used with the
famous AT&T Round Cells (the world's most reliable lead/acid battery) in the
most mission critical battery installations.
Current Limiting Resistor
Batscan makes no direct connections to the battery, instead, a high ohmic protective resistor
is fitted between each battery cell and the measuring leads. The specifications of this resistor
are extreme; Resistance is 2MΩ, and surge pulse capability is in excess of 10kV.
The high resistance ensures that maximum short circuit current is limited to a safe level under
all circumstances.
What is 'Safe Level'?
For human protection a circuit is considered to be safe if the current is limited to 0.7mA.
Batscan is setting a new standard for reliability by using the same level for protection of the monitored battery.
Note! This is the limit in worst case condition, such as short circuit. Normally the measuring
current is in the µA range.
Safe connection to a battery cell with a high ohmic protective resistor.
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Forsmark Nuclear Power Plant in Sweden.
Separate Power Supply
Obviously, the monitoring system must be powered separately in order to work independently of
the monitored battery.
Fiber optic communication
A common computer in the control room may be used for monitoring of both safety classified
and unclassified batteries within the facility by using fiber optic cables between the battery rooms.
User friendly software
The graphical user interface allows for a large number of batteries to be monitored at the same time.
Graphical presentation gives a good overview..
See example with a 10 battery monitoring system:
Arlanda ATCC.
Service & Maintenance
Batscan is also a great tool for periodic battery discharge tests to produce documentation
and logging of battery data.
See example of Battery Discharge Test.
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