Product Data

L404A,B PRESSURETROL® CONTROLLERS
SERVICE INFORMATION
1
INPUT
OUTPUT
ZERO
ADJ
0
W
R
B
SETPOINT
DECREASE
ZERO OHMS
(INFINITY WHEN R-B BREAKS
)
OHMMETER
1
AN L404A, B HAS ONLY TWO TERMINALS (SPST SWITCHING);
AN L404A R C BREAKS AND L404B MAKES WHEN THE SETPOINT IS
DECREASED FAR ENOUGH.
M19539
Fig. 8. Checking controller operation
using an ohmmeter.
Calibration
The controller was carefully calibrated during manufacturing
and should not require recalibration. Most calibration errors
are caused by improper leveling. The controller should be
level when the pointer on the leveling indicator is directly over
the index mark (Fig. 7). In some cases, the leveling indicator
may not be accurate enough. The pointer may be over the
index mark, but the controller still may not be operating within
the tolerance of its scale setting. In this case, carefully bend
the steam trap (siphon loop) until the controller switches
properly.
Maintenance
The cover of the controller should be in place at all times to
protect the internal components from dirt, dust, and physical
damage. Routine maintenance should consist of occasional
inspection and blowing or brushing away any accumulated dirt
and dust. To ensure proper functioning of the controller at all
times, perform an operational check of the entire system
during routine maintenance checks.
Automation and Control Solutions
Honeywell International Inc. Honeywell Limited-Honeywell Limitée
1985 Douglas Drive North 35 Dynamic Drive
Golden Valley, MN 55422 Scarborough, Ontario
M1V 4Z9
Printed in U.S.A. on recycled
paper containing at least 10%
www.honeywell.com
post-consumer paper fibers.
95C-10187B–1 G.R. Rev. 10-03