1.Apply mid-range pressure and note the error between theoretical and actual output signal.
2.Apply full-scale pressure. Multiply the error noted in step 1 by six and by the rangedown factor:
Maximum Allowable Span
Rangedown Factor = --------------------------------------------------------------------
Calibrated Span
3.Add the result to the full-scale output for negative errors, or subtract the result from the full-scale output for positive errors by adjusting the linearity trimmer (see Figure 3-4). Example: At
4-to-1 rangedown the midscale point is low by 0.05 mA. Therefore, adjust the “Linearity” trimmer until full-scale output increases by (0.05 mA 6 4) = 1.2 mA.
4.Readjust zero and span.
NOTE
If you remove either cover during the above procedures, replace the O-ring and torque the cover per the instructions given in Section 5 Maintenance and Troubleshooting. Spare cover O-rings are supplied with each transmitter.
Damping |
Adjustment |
(Optional) |
Linearity |
Adjustment |
Electronics Side of |
Transmitter |
Housing (Cover |
Removed) |
Damping electronics are available as an option. Transmitters with standard electronics can be retrofitted with the adjustable damping feature by changing out both the amplifier board (RMT P/N 01154-0021-0004) and the calibration board (RMT P/N 01154-0023-0002).
