TriPoint VertexRSI 7200, Руководство по эксплуатации и обслуживанию

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2.0 OVE R V I EW OF THE 7200 ACS
2.1 G e n e r a l I nfo r m a t i on About th e 7200 ACS
The 7 2 0 0 A C S i s an antenna po i nt i ng system, contro ll ed manua ll y or automat i ca ll y,
that pos i t i ons the antenna to rece i ve the peak s i gna l from one or more
commun i cat i ons sate lli tes. The 7 2 0 0 A C S uses m i croprocessor techno l ogy to
prov i de accurate antenna pos i t i on i ng, h i gh re li ab ili ty, and max i mum system
f l ex i b ili ty. The system has the capab ili t i es for rap i d mu l t i p l e sate lli te access, h i gh l y
soph i st i cated pred i ct i ve track i ng w i th i nc li ned orb i t sate lli tes, and RS-2 3 2 C, RS-
4 2 2, or IEEE-4 8 8 (Opt i ona l ) remote contro l commun i cat i ons.
In t w o-ax i s app li cat i ons, az i muth (A Z) and e l evat i on (EL) contro l s are used to
pos i t i on the antenna. The three-ax i s app li cat i ons uses A Z, EL, and po l ar i zat i on
(POL) contro l s to pos i t i on the antenna and feed assemb l y. The four-axes uses A Z,
EL, and t w o po l ar i zat i on s (POL & 4 T H A XIS) to contro l the pos i t i on of the antenna
and feed assemb l y. V ar i ab l e speed i nverters prov i de t w o-speed operat i on for A Z
and EL w i th cont i nuous l y var i ab l e dr i ve rates over a range of approx i mate l y 5 0 to 1.
The 7 1 5 0 Dr i ve C ab i net houses the dr i ve contro l s and i nterfac i ng equ i pment to the
7 2 0 0 A C S. The 7 1 5 0 Dr i ve C ab i net i s norma ll y mounted on the antenna
foundat i on.
A l arge 8- i nch by 4- i nch e l ectroum i nescent d i sp l ay and a sens i b l e, unc l uttered
keypad form a user i nterface w h i ch i s fu ll y menu-dr i ven and i nc l udes context-
sens i t i ve he l p messages. W i th much deta il pa i d to the man-mach i ne i nterface, the
7 2 0 0 A C U prov i des stra i ghtforw ard access to an extreme l y versat il e A C S.
The 7 2 0 0 offers a number of operat i ona l modes i nc l ud i ng manua l j og contro l ,
severa l programmed pos i t i on i ng modes, " convent i ona l " steptrack, and the
revo l ut i onary Orb i t Pred i ct i on Track (OPT) mode. OPT prov i des track i ng
performance approach i ng that of monopu l se contro l systems by comb i n i ng eff i c i ent
steptrack operat i on w i th advanced orb i ta l propagat i on a l gor i thms to produce a
state-of-the-art, pred i ct i ve track i ng method. W i th OPT, the 7 2 0 0 prov i des h i gh l y
accurate track i ng w i th m i n i ma l i n i t i a l data approx i mate l y 1.2 5 hours for i n i t i a l
mode l deve l opment).
T w o-speed motor contro l i s prov i ded as standard equ i pment, not through the use of
expens i ve c l utched arrangements or dua l -w ound dr i ve motors, but w i th standard
three-phase i nduct i on motors, contro ll ed by so li d state var i ab l e frequency i nverters.
Th i s approach not on l y prov i des a re li ab l e and cost-effect i ve means of t w o-speed
operat i on (w i th rat i os of up to 5 0 to 1), but a l so a ll o w s for more prec i se pos i t i on i ng
than convent i ona l A l ternat i ng Current (A C) motor contro l systems w h i ch s i mp l y use
contactors to s w i tch motor po w er on and off. Th i s i s a resu l t of the ab ili ty of the
i nverter to " ramp " the motor speed up or do w n i n a contro ll ed manner rather than
s i mp l y remov i ng motor po w er w h il e at fu ll speed. Th i s can resu l t i n uncontro ll ab l e
coast i ng and i nev i tab l e " overshoot " of the target.