Application Guide

Pressure Independent VAV Applications with CSP-4702 19 CTE-5202 Applications Guide, AN0912A Rev. H
Pressure Independent VAV
Applications with CSP-4702
This section describes using the new CSP-4702 VAV
controller-actuators in new installations as well as
in the place of older CSP-5001/5002, CEP-4xxx, and
CSP-40xx/42xx/44xx/46xx VAV controller-actuators.
The CSP-4702 uses a dierential pressure sensor
rather than the ow sensors of the older models. The
dierential pressure sensor provides greater ac-
curacy at low air speeds and is much less aected by
the length and quality of the tubing and connections
to the SSS-1000 series air ow sensors.
NOTE: Air ow volume is determined from
the dierential pressure by the formula
Volume (cfm) = K√ΔP (the K factor of the
VAV box multiplied by the square root
of the dierential pressure in “wc”). The
K factor should be in the information
supplied by the VAV box’s manufacturer.
If using a KMC SSS-10xx sensor, see the
K chart and formulas in the SSS-1000
Series Installation Guide. If using an
SSS-101x sensor (instead of an SSS-100x),
the 3/8" tubing and adapters shown in the
illustration are unnecessary.
CSP-4702
24 VAC CTE-5202
(Used in VAV
applications but
not in static
pressure bypass
applications)
Damper
SSS-100x Sensor
1/4-Inch Tubing
SET
POINT
3/8" Tubing
3/8" to 1/4" Union Adapters
NOTE: For CSP-4702 specications, see the CSP-
4702 Data Sheet. For information on
mounting, wiring, conguration, and other
information, see the CSP-4702 Installation
Guide.
NOTE: In addition to VAV applications, the
CSP-4702 can also act as a static pressure
controller in such applications as AHU/
RTU bypass control. It is not then
connected to a thermostat. See the CSP-
4702 Static Pressure (Bypass) Control
Application Guide for more information.