Oxygen supply system, comprising: a container housing having a container door; oxygen supply equipment held within the container housing and configured to be released through the container door; an electromechanical actuator coupled to a latch of the container door and configured to actuate the latch to releasable open the container door; and a function tester coupled in series to the electromechanical actuator and configured to test the functionality and operability of the electromechanical actuator and to signal a result of the test to a user, wherein the electromechanical actuator comprises a solenoid that includes an electromagnetically inductive coil which is wound at least partially around an armature, wherein the coil of the solenoid is shaped such that upon a current flowing through the windings of the coil the armature alters the electromagnetic field in the vicinity of the solenoid, and the oxygen supply system further comprising: an energy supply coupled to supply interfaces (E1, E2) of the oxygen supply system and configured to provide an electric supply voltage of various voltage levels to the electromechanical actuator, wherein the energy supply is configured in a first operational state to apply a voltage of a first voltage level to the supply interfaces which causes an electric current of a first current level to flow through the solenoid of the electromechanical actuator, the first current level being above an unlatching threshold for unlocking and unlatching the latch by the electromechanical actuator, and wherein the energy supply is configured in a second operational state to apply a voltage of a second voltage level to the supply interfaces which causes an electric current of a second current level to flow through the solenoid of the electromechanical actuator, the second current level being below an unlatching threshold for unlocking and unlatching the latch by the electromechanical actuator, characterized in that the electromechanical actuator further comprises a latch plunger made at least partially of magnetic material and arranged such that a change in the electromagnetic field produced by the solenoid attracts or repels the latch plunger. a container housing having a container door; oxygen supply equipment held within the container housing and configured to be released through the container door; an electromechanical actuator coupled to a latch of the container door and configured to actuate the latch to releasable open the container door; and a function tester coupled in series to the electromechanical actuator and configured to test the functionality and operability of the electromechanical actuator and to signal a result of the test to a user, wherein the electromechanical actuator comprises a solenoid that includes an electromagnetically inductive coil which is wound at least partially around an armature, wherein the coil of the solenoid is shaped such that upon a current flowing through the windings of the coil the armature alters the electromagnetic field in the vicinity of the solenoid, and the oxygen supply system further comprising: an energy supply coupled to supply interfaces (E1, E2) of the oxygen supply system and configured to provide an electric supply voltage of various voltage levels to the electromechanical actuator, wherein the energy supply is configured in a first operational state to apply a voltage of a first voltage level to the supply interfaces which causes an electric current of a first current level to flow through the solenoid of the electromechanical actuator, the first current level being above an unlatching threshold for unlocking and unlatching the latch by the electromechanical actuator, and wherein the energy supply is configured in a second operational state to apply a voltage of a second voltage level to the supply interfaces which causes an electric current of a second current level to flow through the solenoid of the electromechanical actuator, the second current level being below an unlatching threshold for unlocking and unlatching the latch by the electromechanical actuator, characterized in that the electromechanical actuator further comprises a latch plunger made at least partially of magnetic material and arranged such that a change in the electromagnetic field produced by the solenoid attracts or repels the latch plunger.