Gems Sensors Pressure Transmitter Transducer
Very Low Differential Pressure Transducers
Quick Specs...
- For Air or Non-Conductive Gas
- 0.25 to 100 inches in W.C. (differential)/±0.1 to ±50 Inches in W.C. (bidirectional)
- High Proof Pressure
Overview / Design Principle:
The 865 Series are very low-pressure transducers for ranges as low as 0.25" W.C. and feature ±1% full-scale static accuracy. Primarily used in Building Energy Management these transducers are capable of measuring pressures and flows with the accuracy necessary for proper building pressurization and air flow control. 865 Series transducers utilize an all-stainless steel micro-tig welded sensor that allows up to 10 psi overpressure (in either direction) with no damage to the unit. All sensor components have thermally matched coefficients, resulting in improved temperature performance and excellent long-term stability.
How They Operate:
A tensioned stainless steel diaphragm and insulated stainless steel electrode, positioned close to the diaphragm, form a variable capacitor. Positive pressure moves the diaphragm toward the electrode, increasing the capacitance. A decrease in pressure moves the diaphragm away from the electrode, decreasing the capacitance. The change in capacitance is detected and converted to a linear DC electrical signal by Gems Sensors & Controls’ unique electronic circuitry.
Applications:
-
HVAC
-
Energy Management Systems
-
Variable Air Volume and Fan Control (VAV)
-
Environmental Pollution Control
-
Static Duct and Clean Room Pressures
-
Oven Pressurization and Furnace Draft Controls
| Specifications |
| Input |
|
Pressure Range
|
0.25" to 100" W.C.
|
|
Proof Pressure
|
10 psi
|
|
Fatigue Life
|
10 psi, max.
|
| Performance |
|
Supply Voltage (Vs)
|
9-30 Vdc
|
|
Accuracy
|
±1.0% FS (Standard); 0.4% & 0.25% versions available
|
|
Thermal Error Zero
|
±0.033% FS/°F (±0.06% FS/°C)
|
|
Thermal Error Span
|
±0.033% FS/°F (±0.06% FS/°C)
|
|
Compensated Temperature
|
0°F to +150°F (-18°C to +65°C)
|
|
Operating Temperatures
|
0°F to +150°F (-18°C to +65°C)
|
|
Storage Temperatures
|
-40°F to +185°F (-40°C to +85°C)
|
|
Zero Tolerance
|
1% (0.5% for high accuracy option)
|
|
Span Tolerance
|
1% (0.5% for high accuracy option)
|
| Mechanical Configuration |
|
Pressure Port
|
1/4" Fitting
|
|
Wetted Parts
|
Stainless Steel and Glass-Filled Polyester
|
|
Electrical Connection
|
Screw Terminal Strip
|
|
Enclosure
|
Fire Retardant Glass-Filled Polyester; Option A1 Conduit Enclosure Available
|
|
Approvals
|
CE
|
|
Weight
|
3.0 oz
|
| Voltage Output Units |
|
Output
|
0-5 Vdc (See ordering chart)
|
|
Min. Load Resistance
|
5000 k ohms
|
| Current Output Units |
|
Output
|
4-20 mA (2 wire)
|
|
Max. Loop Resistance
|
(Vs-9) x 50 ohms
|
 |
| |
in/mm |
| A |
0.385/10 |
| B |
2.74/70 |
| C |
0.156/4 DIA. Mounting Hole 2 Places |
| D |
3.16/80 |
|
|
 |
| |
in/mm |
| A |
1.64/42 |
| B |
1.89/48 |
| C |
6-32 screw w/Terminal Washers 3 Places |
|
|
 |
| |
in/mm |
| A |
4.33/110 |
| B |
3.34/85 |
| C |
0.61/16 |
| D |
1.41/36 |
| E |
0.875/22 DIA. For Conduit Fitting |
|
|
 |
| |
in/mm |
| A |
1.67/42 |
| B |
1.00/25 |
|
|
 |
| |
in/mm |
| A |
1.94/49.3 |
| B |
1.56/40 |
| C |
1.10/28 |
| D |
2.19/56 |
| E |
0.80/20 |
|
|