The Interface Solution Experts
15
SPA
Site-Programmable RTD &
Thermocouple Limit Alarm Trips
Configure Options
This menu is for selecting display of °C or °F,
linearization on or off, and how the TPRG SPA
behaves in the event of sensor input failure
Figure 8 gives an overview of the menu. To configure
the options of the the TPRG SPA:
1. From the “CONF OPTS” screen of the
Main Menu, press SELECT.
2. Use the arrow buttons to scroll through the
options.
3. Press SELECT when the display shows
the operating parameter that is to be
set, then use the arrow buttons to toggle
between the available settings for each.
4. When the display shows the parameter
set as desired, press SELECT. The next
option or “OPTS EXIT” will be displayed.
5. Repeat step 2, or from “OPTS EXIT” press
SELECT to return to the Main Menu.
“SET FAIL” and the SF3
and AO/AOZ options
The selection made in “SET FAIL” determines how the
SPA functions in the event of a sensor failure. The
SPA’s Total Sensor Diagnostics package distinguishes
between a sensor failure and an alarm condition on
the input, and depending upon which of the available
SPA options is installed, the “SET FAIL” menu can be
used to set the following operating parameters:
• Upscale or Downscale Drive
(when AO or AOZ is installed)
• High Alarms Trip
• Low Alarms Trip
• Relay #3 Trips (when SF3 is installed)
Table 2 summarizes the effect of the SET FAIL setting.
NOTE:
When equipped with the SF3 option,
relays #1, #2, and #4 (if present) freeze in their
respective states (open or closed)
in the event of sensor failure.
Only relay #3 responds to the failure with a
state change.
Table 2. TPRG SPA Function in the Event of Sensor Failure
Standard SPA
(No Options)
SF3-Equipped SPA
AO/AOZ-Equipped
SPA
What is the
“Set Fail” Setting?
“Fail High”
(CONF OPTS menu)
“Fail Low”
(CONF OPTS menu)
“Fail High”
“Fail Low”
“Fail High”
“Fail Low”
Which Alarms trip on
sensor failure?
All High Alarms
(CONF ALRM menu)
All Low Alarms
(CONF ALRM menu)
Alarm #3 if configured as “Hi”
(CONF ALRM menu)
Alarm #3 if configured as “Lo”
(CONF ALRM menu)
All High Alarms
(CONF ALRM menu)
All Low Alarms
(CONF ALRM menu)
How does the Analog Output re-
spon to densor failure?
n/a
n/a
n/a
n/a
Drives output to full scale
Drives output to zero
