KMC Controls FlexStat Operation Guide - Manual (Page 32)

FlexStat 32 Operation Guide, Rev. R
Display Is Blank (or Erratic)
• If the display comes on when a button is pushed,
Display Blanking is enabled. (See (Advanced)
User Interface (UI) on page 21 .)
• Check for a tripped circuit breaker to the trans-
former.
• Carefully remove the FlexStat cover from the
backplate. (See Cover Binds on Backplate on
page 31 .) Check pins and connectors. Ensure the
WD (watch dog) jumper is properly installed on
its two pins closest to the center of the board (see
Firmware Upgrade Failures on page 37 ). Reinstall-
ing the cover on the backplate should restart the
FlexStat if it is supplied adequate power.
• Check for proper supply voltage and phasing
from the transformer and that the transformer
has enough capacity (VA) for all connected
devices. See their respective data sheets and Tips
for Connecting 24-Volt Power Application Note
(AN0604D) .
NOTE: Wiring must be adequate to avoid
excessive voltage drop on long runs!
Allow plenty of “cushion.” A meter may
be too slow to register transient dips or
peaks during startup. See Wiring Issues on
page 39 .
• Put another FlexStat on the installed backplate,
and if the second FlexStat functions properly,
replace the first FlexStat.
• If the FlexStat has been damaged, check the phas-
ing of the power and network lines.See Wiring
Issues on page 39 .
• See also Display Keeps Resetting on page 32 .
Display Freezes (Buttons Have No Effect)
• Carefully remove the FlexStat cover from the
backplate and ensure the WD (watch dog) jump-
er is installed on its two pins closest to the center
of the board (see Firmware Upgrade Failures on
page 37 ). The jumper is temporarily removed dur-
ing a firmware update and should be reinstalled
when the process is completed. Reinstalling the
cover on the backplate will restart the FlexStat.
• If the display is functioning (e.g. time is updat-
ing correctly), but the buttons have no effect
except to turn on the backlight, the FlexStat is in
Locked UI mode. See (Advanced) User Interface
(UI) on page 21 .
• See also (Advanced) CO2 Sensor (and DCV) on
page 11 .
Display Keeps Resetting
• Carefully remove the FlexStat cover from the
backplate, check pins and connectors, and rein-
sert. (See Cover Binds on Backplate on page 31 .)
• Check for proper supply voltage from the
transformer and that the transformer has enough
capacity (VA) for all connected devices (see their
respective data sheets).
NOTE: Wiring must be adequate to avoid
excessive voltage drop on long
runs! Allow plenty of “cushion” in
measurements A meter may be too slow
to register transient dips or peaks during
startup. See Wiring Issues on page 39 .
• Put the FlexStat on a backplate connected to a
(test) transformer with short wiring and no other
connected devices. If the FlexStat works with the
test transformer, the wiring and/or transformer
in its previous location is inadequate. If it does
not work with the test transformer, replace the
FlexStat.
• Put another FlexStat on the installed backplate,
and if the second FlexStat functions properly,
replace the first FlexStat.
“SYSTEM ERROR” Is Displayed
NOTE: The next line is something like “CO2:
COMM ERROR,” and the buttons have no
effect.
• Restart the FlexStat. (See Resetting the FlexStat
on page 26 .) If the buttons don’t function, carefully
remove the FlexStat cover from the backplate and
reinsert it (or cycle the power from the circuit
breaker).
CAUTION
The 6-external-input BAC-12xxxx/13xxxx/14xxxx
series are NOT COMPATIBLE WITH THE
BACKPLATES OF OLDER (3-external-input) BAC-
10000 Series FlexStats! If replacing an older
3-external-input FlexStat, replace the backplate as
well.