Dwyer Instruments 3000 Serie Manual De Instrucciones Y Operación página 2

Bulletin B-33
page 2
INSTALLATION
1. Location
All parts of the Dwyer ® Photohelic
constructed and will stand a moderate amount of vibration, physical
shock, and handling. Normal care in handling and installation is all that
is required. In cases where instrument panel vibration is severe, the
panel should be a spring mounted or the amplifier-relay unit mounted
remotely on a more stable surface.
Select a location where the ambient temperature will not exceed 120°F.
Pneumatic pressure sensing lines may be run any necessary distance.
For example, 250 foot sensing lines will not affect accuracy but will damp
the reading slightly. Do not restrict lines. If pulsating pressure or vibration
causes excessive pointer oscillation or relay chatter, consult factory for
additional damping means.
2. Position
The Photohelic ® Pressure Switch/Gage may be mounted as an integral
package or the amplifier-load relay assembly and housing may be
mounted remotely from the indicating gage-phototransistor unit.
Extension cords with 7 pin plugs and receptacles are available from
Dwyer for interconnection of the two units.
The unit may be mounted in any desired position, scale vertical or
horizontal, without affecting its accuracy, but must be rezeroed if position
is changed from horizontal to vertical or vice versa. The -0 and -00
models must be mounted with the scale vertical.
® pressure switch/gage are ruggedly
Through Panel Mounting
4-13/16˝ (122 mm)
DIA. HOLE REQUIRED
FOR PANEL MOUNTING
3. Mounting
The Photohelic ® Switch/Gage is normally mounted before making
electrical connections, as the electrical enclosure is independent of the
mounting means and may be removed at any time.
Panel Mounting
Normal mounting is flush or through panel is shown in Fig. 2. Be sure to
allow 4-3/8˝ extra space behind the unit for electrical enclosure removal.
Make a single 4-13/16˝ diameter hole in the panel. Insert the entire
Photohelic ® Switch/Gage unit from the front, then slip on the mounting
ring and snap ring from the rear. Seat the snap ring in its groove, back
up the mounting ring against snap ring and tighten the four (4) 2˝ No. 6-
32 clamp screws provided. If behind panel space is critical, the amplifier-
relay unit can be mounted remotely. See the Remote-Relay Mounting
Instructions for details.
SNAP RING GROOVE
1/8˝ MALE NPT PRESSURE CONNECTIONS.
SINGLE HIGH PRESSURE CONNECTION
FOR SERIES 36000A MODELS.
Fig. 2