Dwyer 1620 - Manual

DWYER INSTRUMENTS, INC. Phone: 219/879-8000 www.dwyer-inst.com
P.O. Box 373 • Michigan City, IN 46361-0373, U.S.A. Fax: 219/872-9057 e-mail: [email protected]
Series 1620 – Single and Dual Pressure Switches
Specifications - Installation and Operating Instructions
Bulletin E-51
Model (1626
shown, 1627
similar)
1626-1
1626-5
1626-10
1626-20
Operating
Range
Inches,
W.C.
.15 to 1.5
.5 to 6.0
2.0 to 11
8.0 to 24
Min.
.10
.15
.25
.50
Approximate
Dead Band
Ø9/32 [7.14]
MOUNTING HOLE
TYP 2 PLACES
1-1/2
[38.10]
5-7/8
[149.23]
8-7/8
[225.43]
8-1/4
[209.55]
7-3/4
[196.85]
45 ° TYP
22.5 °
1/8 FEMALE NPT
HIGH PRESSURE
CONNECTION
1/8 FEMALE NPT
LOW PRESSURE
CONNECTION
R 4-5/16 [109.54]
TYP 2 PLACES
3 [76.20]
4-11/16 [119.06]
3-1/16
[77.79]
1-5/16 [33.34]
3/4 [19.05]
1/2 CONDUIT
CONNECTION
Series 1620 Pressure Switch
SPECIFICATIONS
Service: Air and non-combustible,
compatible gases.
Wetted Materials: Consult factory.
Temperature Limits: -30 to 130°F
(-34.4 to 54.4°C).
Pressure Limits: Max. 50 in. w.c.
(12.44 kPa) continuous, 2 psig (13.79
kPa) surge.
Switch Type: 1626, Single-pole
double-throw (SPDT); 1627, two
Single-pole double-throw (SPDT) .
Repeatability: ±1%.
Electrical Rating: 15 A @ 120-480
VAC, 60 Hz. Resistive, 1/8 HP @ 125
VAC,1/4 HP @ 250 VAC, 60 Hz. Electrical Connections: 3 screw type,
common, normally open and normally
closed.
Process Connections: 1/8˝ female
NPT.
Mounting Orientation: Diaphragm in
vertical position. Consult factory for
other position orientations.
Set Point Adjustment: Screw
Adjustment.
Weight: Model 1626, 3 Ib, 9.8 oz (1.64
kg); Model 1627, 3 Ib, 11.8 oz (1.69
kg).
Agency Approvals: CE.
INSTALLATION
1. Switch is normally calibrated for mounting in the vertical position with pressure
and electrical connections pointing down. If other mounting is desired, it should be
specified when ordering.
2. Two lugs with 9/32˝ diameter holes, 180 degrees apart on an 8-1/4˝ diameter
circle are provided.
3. The location selected should be free from excessive vibration and ambient
temperatures should not be above 130°.
OPERATION
1. General – Differential pressure acting on the power diaphragm rotates a
channel, compressing a calibrated spring. The rotation of the channel actuates a
snap switch when the set-point is reached, opening one set of electrical contacts
and closing the other.
2. Pressure Connections – Two 1/8˝ NPT female connections are provided. Make
appropriate connections as follows:
A. Differential Pressure – Connect tubing from source of greater
pressure to high pressure port and from lower source to low
pressure port.
B. Positive Pressure (above atmospheric) – Connect tubing from
pressure source to high pressure port. Leave low pressure port
vented to atmosphere.
C. Negative Pressure (vacuum) – Connect tubing from vacuum
source to low pressure port. Leave high pressure port vented to
atmosphere.
NOTE: When installing switch per paragraphs B or C in dusty
environments, we recommend use of optional A-331 filter vent
plug in the unused port. This will keep excess dirt from collecting
inside switch.
3. Electrical Connections – Make wire connections for normally open or normally
closed operation to appropriate screw terminals on snap switch.
ADJUSTMENT
1. If switch has been furnished pre-set, mount it vertically or horizontally as
specified. Shifting the position of the switch will alter the set point. Because the set-
point may shift in transit it should be checked before placing it in service.
2. The effective area of either side of the power diaphragm is changed by the effect
of the sealing diaphragm. Thus, the actuating differential pressure setting must be
made with the total pressure for the service intended imposed on both sides of the
diaphragm. For example, a switch set to close a circuit at a differential pressure
increase to 1˝ of water with a total pressure of 1 PSIG will vary from the 1˝ of water
setting if the total pressure is increased to 2 PSIG. Also, a two or three percent
variation will be noted if a switch set for vacuum or below atmospheric pressure is
used for pressure or above atmospheric pressure control.
3. To establish the set-point, use a manometer or pressure gage in an appropriate
range and of known accuracy. Apply pressure slowly to allow equalization in all
branches of the system. Keep tubing lengths as short as possible.
4. Model 1626 – The set-point is changed by turning the adjusting nut clockwise to
increase and counter-clockwise to decrease. Model 1627 – The set-point of snap
switch No. 2 is established first using the adjusting nut as with the 1626 series.
Next, set snap switch No. 1 by turning the adjusting screw under the switch roller.
Recheck switch No. 2 and correct as necessary. If switch No. 2 needs re-
adjustment a final check of switch No. 1 should be made. The settings of the two
switches affect one another and both should be checked any time either is
changed.
MAINTENANCE
No unusual precautions are required. Care should be taken to keep the switch
reasonably dry and free from dust or dirt. No lubrication required.
CAUTION: For use with air or compatible gases only.
Max.
.20
.35
.65
1.20
Adj. Diff.
Between Set
Points
(1627 only)
0.5
1.2
2.3
5.0
MODEL 1626, ALSO MODEL 1627 DUAL SWITCHES:
OPERATING RANGES, DEAD BANDS AND RATINGS.
Add –EXPL for explosion proof housing;
Add –WP for weather proof housing.
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