148. 5V AC External power supply (optional)Set up the power supply in the following manner:Remove the plastic cover (ifapplicable). (picture 23)Select a suitable plug fromthe four alternatives.(picture 24)Plug in the plug and ensurethat it is not loose. (picture25)The control unit has been designed and tested to be used with the Globtek inc.power supply (see chapter Technical Specifications for details). Using any otherpower supply may interfere with the safe use of the device.When the power supply is connected, the batteries act as backup power supplyin the event of a power failure. All alkaline batteries self-discharge and start toleak when empty, contaminating the device. Ensure that batteries are replacedat least once a year.When removing the power supply from the socket, ensure that the plug part isnot left in the socket. If the plug part is left in the socket, touching or trying toremove it carries the risk of an electric shock.Keep device cords out of the reach of children (risk of strangulation). Useprotective cord covers or cable ties to securely attach and hide cords to preventstrangulation. Keep cords as short as possible and secure them so that they areout of reach of children.