Emerson Process Management Bristol Series 9110 - Manual (Page 30)

Board Setup 3-6 CI-9110
Table 3-3 - Switch SW2 (2-5), Output Rate Of Change
SW2-5 SW2-4 SW2-3 SW2-2
Nominal
Rate Of Change, ±15%
Close Close Close Close 1.8 Min. Full Scale Travel
Close Close Close Open 5.5 Min. Full Scale Travel
Close Close Open Close 11.0 Min. Full Scale Travel
Close Close Open Open 16.5 Min. Full Scale Travel
Close Open Close Close 21.9 Min. Full Scale Travel
Close Open Open Close 32.9 Min. Full Scale Travel
Close Open Open Open 38.3 Min. Full Scale Travel
Open Close Close Open 43.8 Min. Full Scale Travel
Open Close Open Open 60.3 Min. Full Scale Travel
Open Open Close Close 65.85 Min. Full Scale Travel
Open Open Close Open 69.4 Min. Full Scale Travel
3.7 ANALOG FAILURE MODES (Fail Hold & Fail Zero)
Analog models have an "Analog Fault Detector" feature which, when selected by jumpers on
the Termination Board, provides a selection of two failure modes, Fail Hold and fail Zero. In
the "Fail Hold" mode, the Analog Fault will stop the stepper motor at the last pressure
output value prior to the loss of the analog input signal. Note that the Guard terminals are
not available for external usage in this mode. The Fault Detector trip point for this mode is
factory set at 0.8 volts which corresponds to -5% of fullscale.
In the alternate "Fail Zero" mode, the Guard terminals are available for use with an
external signal. In this mode, the analog input signal is “enabled” by a signal at the Guard
terminal. If the input drops to zero while the Guard signal remains TRUE, the output will
also go to zero.
The selection of either failure mode is accomplished via two jumpers, W1 and W2. These
jumpers are located on the Termination Board as shown in Figure 3-2. These jumpers may
be plugged in position A or B; however, both jumpers must always be in the same position.
The configurations are selected as follows:
FAIL-HOLD MODE
(Both Jumpers in A position)
In the "A" position, a failure of the AI Command Input (value fails below 0%) causes the
pressure output to remain at the value of the last valid sampling period. This condition is
maintained until a normal AI is received.