TriPoint VertexRSI 7200, Руководство по эксплуатации и обслуживанию

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T W O-SPEED RES OLV ER C ALIBRA TIO N
D - 3
A PP END I X D - TWO-S P EED R ESO L VE R CA L I B R AT I ON
1.0 I nt r odu c t i on
Th i s append i x conta i ns i nstruct i ons for ca li brat i ng the t w o-speed reso l vers (t w o-
speed reso l ver opt i on on l y) i n the 7 2 0 0 A C S.
2.0 S e tt i ng Ex c i t a t i on Vo l t a g e
The t w o-speed system used on the 7 2 0 0 A C U i s stab l e to w i th i n + /-0.0 0 0 5
degrees, hence bobb l e i n the l ast one one-thousandth pos i t i on may be present, but
on l y by one count. A n excess i ve bobb l e of more than 0.0 0 1 degree i s usua ll y
caused by e i ther poor or i nsuff i c i ent env i ronmenta l sh i e l d i ng or l o w exc i tat i on
vo l tage (prov i d i ng there are no mechan i ca l prob l ems). The fo ll o w i ng procedures
descr i be ho w to check the exc i tat i on vo l tage; sh i e l d i ng i s d i scussed i n A ppend i x G,
Troub l eshoot i ng Gu i de, of th i s manua l .
1. Turn off the po w er to the 7 2 0 0 A C U and s li de i t forw ard from the rack.
Remove the four # 6-3 2 scre w s ho l d i ng the front of the top li d and li ft the li d,
l ock i ng i t i n p l ace w i th the h i nge found on the r i ght s i de of the sub-rack i ns i de
the un i t.
2. Po w er up the un i t and d i sab l e the dr i ves us i ng the front DRIV E EN A BLE s w i tch
as a precaut i onary measure. D i sconnect the 5 0-conductor r i bbon cab l e go i ng
to the r i ght s i de of the 8 0 0 2 5 2 I/O card; expos i ng a sma ll b l ue tr i mpot on the
8 0 0 2 2 5-0 2 RD C card. Th i s tr i mpot ad j usts the reso l ver exc i tat i on vo l tage
l eve l w h i ch can be measured at the t w o-term i na l connector at the bottom of
the back pane l .
3. Use an A C RMS vo l tmeter to set the vo l tage to at l east 4 V RMS. If the
bobb l e pers i sts, ra i se the vo l tage up to a max i mum of 9 V RMS. Th i s shou l d
correct the prob l em on standard run l engths. If the bobb l e pers i sts or does not
d i m i n i sh, a bad sh i e l d or s i gna l w i re connect i on may be the prob l em.
4. Reconnect the 8 0 0 2 5 2 5 0-conductor r i bbon cab l e assemb l y, re-enab l e the
dr i ves, and ver i fy that no dr i ve cab i net re l ated errors are occurr i ng. Resecure
the top li d, s li de un i t back i n rack, and resecure the un i t us i ng the # 1 0-2 4 cup
head scre w s.