Table of Contents
Advertisement
1MRS750881-MUM
5.2.3.
5.2.4.
Remote Monitoring and Control Unit
Technical Reference Manual
Condition monitoring of batteries
The condition of the batteries is secured by a periodic ten second load test, which is
performed twice an hour and always after the power up of the device. The test can
also be activated remotely with the parameter Battery test.
The status of the battery test, that is, whether the test is active or not, can be read via
remote communication with the parameter BatteryTestSta. The corresponding
global variable in the Relay Configuration Tool is the following:
• REC 523: PSC_7_BattTest
During the battery load test, the voltage of the power supply charger is reduced to
20 V, which causes the electronics and communication to load the batteries. The
automatic functions of the device measure the battery voltage continuously also
during the test.
If the battery voltage drops to ~21...23 V during testing, the device generates an
alarm to indicate that the lifetime of the batteries is ending or that an internal battery
fault has occurred, which means that the battery must be changed in the near future.
The status of the battery can also be read via remote communication with the
parameter Battery status. The corresponding global variable in the Relay
Configuration Tool is the following:
• REC 523: PSC_7_BattStatus
The parameter Minimum battery voltage indicates the lowest battery
voltage recorded, which is usually the voltage during a control operation. The
recorded voltage can be used to estimate the condition of the batteries. Note that the
parameter must be set via remote communication to correspond to the present
battery voltage when a new battery has been installed.
Battery charger
The power supply of the REC 523 device includes a temperature-compensated
battery charger. The charger secures a suitable charging voltage in different
environmental conditions. The batteries are also protected against too high or too
low charging voltages.
The charger regulates the charging voltage for the batteries according to the
temperature as illustrated in the figure below.
The output of the battery charger is protected by a fuse located on the printed circuit
board of the module.
REC 523
27
Advertisement
Table of Contents
