Series 3000SGT Photohelic® Pressure Switch/Gage with Integral Transmitter

Photohelic® Pressure Switch/Gage with Integral Transmitter
Indicating Gage, Low and High Limit Control, 4-20 mA Transmitter

Indicating Gage, Low and High Limit Control, 4-20 mA Transmitter

The Series 3000SGT Photohelic® Switch/Gage/Transmitter combines several critical control functions into a single, easy-to-install package. This versatile instrument starts with the universally accepted standard for reliable low air pressure measurement, the Dwyer® Magnehelic® Gage. It measures positive, negative or differential pressures within ±2% of full scale accuracy. This time-proven component provides highly reliable analog indication of air or compatible gas pressure on a 4", 80° scale. Gage operation is completely independent — functions normally even if power is interrupted to electrical elements of the control.

Next, two DPDT relays are added which serve as Low/High limit controls (or pressure switches) capable of handling up to 10 amps @ 28 VDC or 120/240 VAC directly. Individual set point deadband is one pointer width — less than 1% of full scale; just enough to assure positive, chatter-free operation. Integral holding coils enable user to connect the two so they work like a single control with variable deadband — ideal for applications such as clean room and building pressurization, HVAC systems, automatic air filter or level control and much more. Actuation points are fully adjustable over the entire pressure range with convenient front mounted knobs linked to bright red set point indicators.

Finally, the Series 3000SGT Photohelic® Switch/Gage includes a separate 4-20 mA, 2-wire transmitter operating from an external 10-35 VDC power supply. Separate adjustments are included for zero and span inside the rear electronics enclosure. Optional A-700 Power Supply is a perfect companion rated for AC inputs from 100-240V; DC outputs from 24-28V. The transmitter component is an ideal driver for variable speed blowers and fans, damper positioners and for continuous data logging on computerized VAV systems or strip chart recorders.

Besides the obvious cost and space saving advantages of combining all these control functions in a single unit, think of the additional savings in time and material with just one set of pneumatic lines to connect instead of three or four.

This product is being phased out, see Series 605 or Series DH3 for suggested replacements.

More Information
Model Chart
EXAMPLE 3000SGT-0 24VAC Series 3000SGT-0-24VAC Photohelic® Pressure Switch/Gage with Internal Transmitter, range 0-0.5" w.c., with 24VAC relay pack.
RANGE 3000SGT-0
3001SGT
3002SGT
3003SGT
3006SGT
3010SGT
3020SGT
3030SGT
3200SGT
3000SGT-250PA
3000SGT-500PA
3000SGT-1.5KPA
  0-0.5" w.c.
0-1" w.c.
0-2" w.c.
0-3" w.c.
0-6" w.c.
0-10" w.c.
0-20" w.c.
0-30" w.c.
0-200" w.c.
0-250 Pa
0-500 Pa
0-1.5 kPa
OPTIONS   24VAC
230VAC
AT
COO
G
HC
HL
LH
LL
LT
M
NIST
R
ST
TA
TAMP
WP
Y
24 VAC Relay Pack
220/240 VAC Relay Pack
Aluminum Tag
Certificate of Origin
Green Scale Overlay
Horizontal Calibration (90° face up)
Latching (high/low)
Latching Option (low/high)
Latching Option(low/low)
Low Temperature
Mirror Scale Overlay
NIST Certificate of Calibration
Red Scale Overlay
Stainless Steel Tag
Tilt Angle from Vertical in Degrees (-90 to 90)
Tamperproof Knobs
Weatherproof Housing
Yellow Scale Overlay
Options
  • -TAMP Tamper-Proof Knobs - require special spanner-type key (included) to adjust set points.
  • -LT Low Temperature Option, 0°F (-18°C).
GAGE SPECIFICATIONS
Service: Air and non-combustible, compatible gases.
Wetted Materials: Consult factory.
Accuracy: See model chart on catalog page.
Pressure Limits: See model chart on catalog page.
Temperature Limits: 20 to 120°F (-6.67 to 48.9°C).
Process Connections: 1/8" female NPT.
Size: 4" (101.6 mm) dial face, 5" (127 mm) O.D. x 8-1/4" (209.55 mm).
Weight: 3 lb. 14.5 oz (1.77 kg).
SWITCH SPECIFICATIONS
Switch Type: Each set point has 2 Form C relays (DPDT).
Repeatability: ±1% of full scale.
Electrical Rating: 10A @ 24 VDC or 120 VAC, 6A @ 240 VAC.
Electrical Connections: Screw terminals.
Power Requirements: 120 VAC, ±10%.
Mounting Orientation: Diaphragm in vertical position. Consult factory for other position orientations.
Set Point Adjustment: Adjustable knobs on face.
TRANSMITTER SPECIFICATIONS
Accuracy: See model chart on catalog page.
Temperature Limits: 20 to 120°F. (-6.67 to 48.9°C).
Pressure Limits: See model chart on catalog page.
Thermal Effects: ±0.025% F.S./°F (0.045% F.S./°C).
Power Requirements: 10.0 to 35 VDC (2-wire).
Output Signal: 4-20 mA DC.
Zero & Span Adjustments: Multi-turn potentiometers, internally accessible.
Response Time: 250 mSec.
Loop Resistance: 0 - 1250 ohms.
Current Consumption: 38 mA DC, maximum.
Electrical Connections: Terminal block.
Warm-up Time: 10 minutes.