Device Description HG G-71912-A | English, Revision 03 | Date: 28.03.2018
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Components and Operation – Chapter 5
5
Components and Operation
5.1 Underground components
Transponders of the type HW DEV00095/HW DEV00098 or HG G-71325XA may be used as
reference points. All described RW transponders can be programmed using the reading an-
tennas or an optional programming device of the type HG G-81830YA.
Range and accuracy of the system are influenced by:
–
any large metal pieces (sheets) on the ground
–
proximity of any floor reinforcement (see chapter 3 „Mounting“ on page 8, section 3.1
„Transponder“ on page 8)
–
Inductive loops, as they are created e.g. by steel building mats have a great influence.
Individual metal poles have little effect. Those may be partly within the metal-free
area (see Figure 2 on page 8).
–
Cable with pulsed currents with spectral parts between 64 kHz ±4 kHz
–
The following environmental conditions have no effect on the system:
–
Snow, ice, water
–
Oil, tar, earth, dirt, etc.
Code structure
The code length is 20 bit of useful data. The system decodes and outputs the entire code
string; when using the parallel interface only the 15 lowest bits are output. The data protec-
tion within the trovan™ transponders is done by line (of 3 bit each) and column parity. To
achieve a better data protection, it is therefore recommended to implement an additional
code check when using RW transponders. The transmission duration for one complete tele-
gram is 8 ms for both types.
