The power supply of the C50 has two Li-Ion batteries and uses the highest voltage battery, switching is automatic. The INFRA C50 unit is only to be used with Sigicom B100 Li-ion batteries.

Insert the batteries by opening the side panel using T20 Torx screwdriver and put them into position.
It is possible to change batteries while in operation, even if the sound measurements will be affected by the operator.
Replace one battery at a time with new batteries. The batteries can be removed by hand.
Put back the battery lid and reassemble the T20 Torx screws firmly.

Getting started