Portable Power Module for Güralp Certimus
Operation
6 V, at which point it will automatically shut itself off in order to protect the cells
from damage.
Note:
If the PPM is operated until it has shut itself down due to low
battery voltage, it must then be recharged to at least 6.4 V before the
output power is turned on again.
The initial charge on the battery limits the duration of the deployment so it is
important to fully charge the PPM prior to installation. This maximises the "up-
time" of the system. Monitor the supplied current when charging the PPM: this will
fall to zero and charging will automatically stop when the battery voltage reaches
approximately 8.4 V.
Provided that the PPM has sufficient charge and has been woken up (see section 4.1.1
on page 7), it is only necessary to connect the PPM’s Power Out to the Certimus’
Power Input (using the supplied cable). The PPM will then immediately output
power to the Certimus without requiring further action.
4.3.2 Charging
The PPM can be charged using an DC power supply capable of providing a voltage
between approximately 10 and 32 volts. The PPM is fitted with over-voltage
protections so, if the input voltage exceeds 36 V, charging will be disabled in order to
protect the cells.
Note:
Because of the MPPT function (see section 4.2.3.2 on page 14), if the
input voltage is suddenly reduced, the input current may drop to zero for a
short period while the MPPT controller adjusts the input impedance to
suit.
Caution:
If the PPM has been left totally discharged for a very long time, it
will need to be reconditioned in order to avoid damaging the cells. The
reconditioning process involves structured charging with a very low
initial current. Please seek advice in this situation.
15
Issue A - May 2021
