IDTECK LX007, Manual, Page: 27 / 107

p.19 Check Point during Installation
arth grounding; however bringing the earth ground to the communication cable isn’t easy a
nd the installation cost increases. There are three grounding points you can find during insta
llation;
1. Earth Ground 2. Chassis Ground 3. Power Ground
The most important point about grounding system is not to connect both ends of shield wir
es to the grounding system; in this case, there will be a current flow through the shield wire
when the voltage level of both ends of shield wire is not equal and this current flow will intr
oduce some noise and interference to communications. For better grounding, we advise you
connect ONLY one end of shield wire of communication cable to the grounding system; If y
ou find earth ground nearby, then connect one end of the shield wire to the earth ground; I
f you do not have earth ground nearby, then find chassis ground and connect one end of sh
ield wire to chassis ground; If you do not find either earth ground or chassis ground, then co
nnect one end of shield wire to power ground. (GND of LX007) Note that if the chassis grou
nd is not properly connected to the earth and floated from the ground level, then groundin
g to the chassis ground will give the worst communication. Therefore, we recommend you u
se power ground instead of chassis ground if that is the case.
2.4 Reverse Diode Connection
If you connect an inductor (Door Locks or Alarm device) to the output relays, there will be a
high surge voltage created while the inductor is turning on and off. If you do not connect a r
everse diode, the surge voltage will transfer and damage the electronic circuit of the controll