GE Masoneilan 4700E, Maintenance Manual

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Masoneilan 4700P/E & 4800P/E Positioners Manual =
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5. Apply low value of instrument signal. (3 psi if 3-15 psi signal range) Unlock zero
locknut (4C) and turnbuckle locknut (107). Adjust zero by turning both the zero nut
(4B) and turnbuckle (106) until the low signal line of the cam is aligned with the
positioner case raised reference line and the travel indicator shows
opened
position. Refer to Figure 5 on page 23 and Figure 19 on page 68. Re-tighten both
locknuts.
6. Apply full scale value of instrument signal (i.e. 15 psi) and note position of stroke
scale indicator. If travel is not correct, perform span adjustment. Refer to “Span
Adjustment” on page 48.
7. Repeat zero and span adjustments per “Zero Adjustment” on page 48 and “Span
Adjustment” on page 48 until travel range is correct. After adjustments are
satisfactory, re-tighten the spring locking screw (8), zero locknut (4C), and
turnbuckle locknut (107).
Air to Close / Direct Acting Positioner
See Figure 19 on page 68 and Figure 20 on page 71.
1. Apply lower value of instrument signal (i.e. 3 psi if 3-15 psi 4700P/4800P or 4 mA if
4-20 mA 4700E/4800E).
2. Unlock zero locknut (4C) and turnbuckle locknut (107). Adjust zero by turning both
the zero nut (4B) and turnbuckle (106) until the low signal line of the cam is aligned
with the positioner case raised reference line and the travel indicator shows
opened position. Refer to Figure 5 on page 23 and Figure 19 on page 68.
Re-tighten both locknuts.
3. Apply full scale value of instrument signal (i.e. 15 psi or 20 mA.) and note position of
travel indicator. If travel is not correct, perform span adjustment. Refer to “Span
Adjustment” on page 48.
4. Repeat zero and span adjustments per “Zero Adjustment” on page 48 and “Span
Adjustment” on page 48 until travel range is correct. After adjustments are
satisfactory, re-tighten the spring locking screw (8), zero locknut (4C), and
turnbuckle locknut (107).