OPM_GTU_19X_1K0_3K0_XUS_V014 17 GT-UL Series: User manual 1.2 (US)Digital Energy ™ GT SeriesgApart from the SNMP-option described in 4.4 the following options are possible:5.1 Extended RuntimeExtended runtime can be obtained by connecting a separate battery extension module to theUPS. The additional batteries increase the runtime and recharging time for the unit, all otheroperational information is the same as for standard models.5.2 TVSS (Transient Voltage Surge Suppressor)RJ-45/RJ-11 Surge Protector.To prevent damage caused by surges, noise and spikes traveling over the telephone line ornetwork line.6.1 General MaintenanceApart from battery servicing, the UPS is virtually maintenance free. Take care of properenvironmental conditions and keep air inlets/outlets free of dust. Please read 1.3.6.2 Batteries - GeneralThe service life of the battery is from 3 to 6 years, depending on the operating conditions(mainly temperature and number of discharge cycles).As a healthy battery is critical to the performance of the UPS, it is advised to regularly performa battery test to ensure failsafe operation (see section 3.3.3). When the condition of the batteryis critical, a 'replace battery' alarm will be activated (see 3.1, LED 11). Replace the batteries assoon as possible. See 6.3.6.3 Batteries - Replacement• WARNING: first read the safety rules in sections 1.1, 1.2 and 1.4.• Servicing of batteries should be performed or supervised by personnelknowledgeable of batteries and the required precautions. Keep unauthorizedpersonnel away from batteries.6.3.1 Battery replacement procedure 1kVA1 Remove front panel2 Unscrew five bolts of the battery compartment3 Unplug battery connectors4 Unscrew one bolt5 Pull out the battery setand renew it6 Assemble UPSby reverse procedure.Fig. 6.15 - Optional Features6 - Maintenance