Honeywell CVL4022ASVAV1 Engineering Manual page 12

.
TOP TABS
BOTTOM FLEX
CONNECTORS
Fig. 8. Controller DIN rail mounting (CVL4024NS-VAV1).
IMPORTANT NOTE:
To remove the controller from the DIN rail, perform the
following:
1. Push straight up from the bottom to release the top tabs.
2. Rotate the top of the controller out towards you and pull the
controller down and away from the DIN rail to release the
bottom flex connectors.
Piping
Air flow Pickup
Connect the air flow pickup to the two restrictor ports on the
controller (see Fig. 9).
NOTES:
—Use 1/4 inch (6 mm) outside diameter, with a 0.040 in. (1
mm) wall thickness, plenum-rated1219 FR (94V-2) tubing.
—Always use a fresh cut on the end of the tubing that
connects to the air flow pickups and the restrictor ports on the
controller.
Connect the high pressure or upstream tube to the plastic
restrictor port labeled (+), and the low pressure or
downstream tube to the restrictor port labeled (-). See labeling
in Fig. 11. When twin tubing is used from the pickup, split the
pickup tubing a short length to accommodate the connections.
NOTES:
—If controllers are mounted in unusually dusty or dirty
environments, an inline, 5-micron disposable air filter (use 5-
micron filters compatible with pneumatic controls) is
recommended for the high pressure line (marked as +)
connected to the air flow pickup.
—The tubing from the air flow pickup to the controller should
not exceed three feet (0.914 m). Any length greater than this
will degrade the flow sensing accuracy.
—Use caution when removing tubing from a connector.
Always pull straight away from the connector or use diagonal
cutters to cut the edge of the tubing attached to the connector.
Never remove by pulling at an angle.
31-00083—02
DIN RAIL
M16815A
Wiring
All wiring must comply with applicable electrical codes and
ordinances, or as specified on installation wiring diagrams.
Controller wiring is terminated to the screw terminal blocks
located on the top and the bottom of the device.
WARNING
Electrical Shock Hazard.
Can cause severe injury, death or property
damage.
Disconnect power supply before beginning wiring or making
wiring connections, to prevent electrical shock or equipment
damage
NOTES:
—For multiple controllers operating from a single transformer,
the same side of the transformer secondary must be
connected to the same power input terminal in each controller.
Controller configurations will not necessarily be limited to
three devices, but the total power draw, including accessories,
cannot exceed 100 VA when powered by the same
transformer (U.S. only). For power and wiring
recommendations, see "Wiring" on page 15. The earth ground
terminal (terminal 3) must be connected to a verified earth
ground for each controller in the group (see Fig. 14 on
page 16).
—All loads on the controller must be powered by the same
transformer that powers the controller itself. A controller can
use separate transformers for controller power and output
power.
–Keep the earth ground connection (terminal 3) wire run as
short as possible.
—Do not connect the universal input COM terminals, analog
output COM terminals or the digital input/output COM
terminals to earth ground. Refer to Fig. 12-Fig. 14 for wiring
examples. The 24 Vac power from an energy limited Class II
power source must be provided to the controller. To conform
12
AIR FLOW
PICKUP
CONNECTOR
TUBING
RESTRICTOR
RESTRICTOR
PORT
PORT
ΔP
1 1 1 1 1 1 1 2 2 2 2 2
3 4 5 6 7 8 9 0 1 2 3 4
1 1
1 2 3 4 5 6 7 8 9 0 1 2
Fig. 9. Air flow pickup connections
M33633