Cleveland Controls
DIVISION OF UNICONTROL INC.
1111 Brookpark Rd.
Cleveland OH 44109
Tel:
216-398-0330
Fax:
216-398-8558
Web page:
http://www.clevelandcontrols.com
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Cleveland Controls
Division of UniControl Inc
.
Bulletin LTAFS460-10
APPLICATION
The
Model AFS-460
is a general purpose
proving switch with a
manual reset
feature
that requires operator intervention whenever
it actuates. It can be used to sense positive,
negative, or differential air pressure in HVAC
and Energy Management applications that
require operator interface.
GENERAL DESCRIPTION &
OPERATION
The plated housing contains a diaphragm, a
calibration spring and a snap-acting SPST–
NC
switch with a manual reset button.
The sample line connections located on
each side of the diaphragm accept ¼" OD
rigid or semi-rigid tubing via the integral
compression ferrule and nut.
An enclosure cover protects the operator
from accidental contact with the live switch
terminal screws and the set point adjusting
screw. The enclosure cover has a
⅞
" opening
provided to accept a ½" conduit connection.
MOUNTING (SEE FIGURE 1)
Select a mounting location which is free from
vibration. The
AFS-460
must be mounted
with the diaphragm in any vertical plane in
order to obtain the lowest specified operating
set point. Avoid mounting with the sample
line connections in the "up" position. Surface
mount via the two
3
⁄
16
" diameter holes in the
integral mounting bracket. The mounting
holes are 3-
⅞
" apart.
(Figure 1)
The sample line connections located on
each side of the diaphragm accept ¼" OD
rigid or semi-rigid tubing via the integral
compression ferrule and nut. However, an
optional adapter (P/N 18311) is available for
slipping on ¼" ID flexible tubing For sample
lines up to 10 feet, ¼" OD tubing is accept-
able. For lines up to 20 feet, use ¼" ID tub-
ing. For lines up to 60 feet, use ½" ID tubing.
Locate the sampling probe a minimum of
1-½ duct diameters downstream from the air
source. Install the sampling probe as close to
the center of the airstream as possible. Refer
to
Figure 2
to identify the high pressure inlet
(
H
) and the low pressure inlet (
L
). Select one
of the following five application options, and
connect the sample lines as recommended.
POSITIVE PRESSURE ONLY:
Connect the
sample line to inlet
H
; inlet
L
remains open
to the atmosphere.
NEGATIVE PRESSURE ONLY:
Connect
the sample line to inlet
L
; inlet
H
remains
open to the atmosphere.
TWO NEGATIVE SAMPLES:
Connect the
higher negative sample to inlet
L
. Connect
the lower negative sample to inlet
H
.
TWO POSITIVE SAMPLES:
Connect the
higher positive sample to inlet
H
. Connect
the lower positive sample to inlet
L
.
ONE POSITIVE AND ONE NEGATIVE
SAMPLE:
Connect the positive sample
to inlet H. Connect the negative sample to
inlet L.
Model
AFS–460
ADJUSTABLE SET POINT AIR PRESSURE SENSING SWITCH WITH MANUAL RESET
AIR SAMPLING CONNECTION
(SEE FIGURE 2)
