User Manual
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Important!  If you want to change a number in the alarm list you must also write in all the other 
numbers in the Alarm list. The unit will only store the information in the last Alarm list sent. 
Activate and deactivate the alarm function 
When the unit starts up by connecting it to a wall socket the alarm function is not activated by 
default. To activate the alarm function you must send a command to the unit, see Controlling the 
unit on page 17. To deactivate the alarm function you must also send a command. 
The power fail alarm is by default activated. If you want to deactivate it, use the command Powerfail, 
see Functions on page 12. 
Acknowledge alarms 
When an alarm has been sent after an alarm sensor has been activated you must acknowledge the 
alarm before the unit will send another alarm message. No alarm sensor shall be active when the 
alarm is acknowledged. See how to do this under Controlling the unit on page 17. You can also 
acknowledge the alarm by pushing the button on the unit. 
Temperature alarms cannot be acknowledged. The unit automatically reset the alarm when 
temperature reach the set temperature plus or minus one degree. 
Powerfail alarms and Battery alarms cannot be acknowledged. 
Wired alarm sensors 
Different types of wired alarm sensors can be connected to Ontech GSM 9025. The unit has two 
alarm inputs. Default setting is Normally Open (NO). If the alarm sensors you connect are of the type 
Normally Closed (NC), you have to set this (See Functions on page 12). 
Connecting a wired alarm 
The alarm sensor is connected to terminal A (See picture on page 9). 
On the picture below it is shown how the alarm sensors should be connected. The plus cable is 
connected to one of the sensors output connectors and input A or B is connected to the other. 
Important! The 3.8V output is only made for the alarm wire and not for powering an extern alarm 
sensor. 
Figure 2 Two alarm sensors with closing function  Figure 3 Two alarm sensors with breaking function 
Important! If the unit is set to alarm at a breaking function (Normally Closed) and only one alarm 
input is used, the other alarm input must bridge to the positive input. If not the unit will assume that 
an alarm sensor is activated and will trigger the alarm. 










