Sturtevant Richmont Programmable Torque Verifier FM II, Руководство пользователя

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Page 31
Chapter 6 - FM Communications
Principles
The PTV-FM and FM Switch Wrench work together as a system using FM radio signals in the
900 MHz band as the medium of communication. There are several ramifications to this:
1. The FM Switch Wrench must have a useable battery in it.
2. The antenna on the PTV-FM must be installed.
3. Both the PTV-FM and the FM Switch Wrench must be set to the same channel.
4. The PTV-FM Generation II must have the power on.
5. The PTV-FM must not be in “Suspend” status, where it ignores wrench signals.
6. The “seed code” transmitted by the wrench must have been “learned” by the PTV-FM.
7. The FM Switch Wrench must be located within 50 feet (15m) of the PTV-FM.
8. FM radio signals are “line-of-sight”; intervening structures can disrupt communications.
The vast majority of the problems encountered with the system result from one of these basic
requirements being unmet.
“Learning” the code transmitted by each wrench was covered in Step 24 of the procedure for
programming the Generation II. This must be performed every time a wrench transmitter is
added to the system or replaced on a current wrench.
The Generation II can hold in memory the codes for up to four wrench transmitters. The method
by which they are held is “rolling”; addition of a fifth transmitter wipes out of the memory the first
transmitter learned. The sixth transmitter learned eliminates the memory of the second transmit-
ter learned, and so forth.
If changing wrenches or replacing transmitter boards, always make sure that all wrenches to be
used with the unit are communicating properly.
Channel Selection
Channel selection is made based upon reliability of communication between the FM Switch
Wrench and the PTV-FM Generation II unit. In some facilities any channel will work well, in oth-
ers there may be only one or two that provide the necessary reliability. If the initial factory set-
tings do not achieve the goal of reliability in the facility where the system will be used, experi-
mentation will be needed to determine the optimum settings.