Compare Description Drawings, CAD & Specs Full Scale Range Analog Output Fitting Type Avail. Price
228A Baratron® 0.2-1000 Torr Differential Capacitance Manometers with 2 Trip Points228A11TBBBBFB3C0AA10 Torr0 - 5 VDC0.25 in. OD tube
$1,187
228A Baratron® 0.2-1000 Torr Differential Capacitance Manometers with 2 Trip Points228A12KBGBGFB7C1BB100 kPa0 - 5 VDC0.1875 in. OD tube
$1,286
228A Baratron® 0.2-1000 Torr Differential Capacitance Manometers with 2 Trip Points228A22MGABBSU2C200200 mbar0 - 10 VDCISO-KF and 0.25 in. OD tube
228A Baratron® 0.2-1000 Torr Differential Capacitance Manometers with 2 Trip Points228A51WCBCBFB5C1AB50 in. H2O0 - 1 VDC4 VCR male

Configuration Options

The following options are available for the 228A Baratron® Differential Capacitance Manometer.
Ordering Code Example: 228AXXXYYZZQSSTVRR

Configuration Option Option Code
228A Baratron Differential Capacitance Manometer 226B
Pressure Range
0.02 (kPA only) U2
0.1 (kPA & inH2O only) .1
0.2 (not available inH2O) .2
0.5 (kPA & inH2O only) .5
1 01
2 02
5 05
10 11
20 21
50 (not available for kPA) 51
100 12
200 (not available for kPA & inH2O) 22
500 (inH2O only) 52
1000 (not available for kPA & inH2O) 13
Engineering Units
Torr/mmHg T
mbar M
kPa K
inH2O W
cmH2O R
Reference Side Fitting (compatible with)
0.25 in. OD tube BB
0.1875 in. OD tube BG
4 male VCR CB
4 female VCR CD
4 male VCO DC
4 female VCO DD
0.25 in. female NPT FA
0.25 in. male NPT FB
0.125 in. male NPT FE
0.125 in. female NPT FF
NW16 KF GA
1.33 in. OD Conflat HA
Measurement Side Fitting (compatible with)
0.25 in. OD tube BB
0.1875 in. OD tube BG
4 male VCR CB
4 female VCR CD
4 male VCO DC
4 female VCO DD
0.25 in. female NPT FA
0.25 in. male NPT FB
0.125 in. male NPT FE
0.125 in. female NPT FF
NW16 KF GA
1.33 in. OD Conflat HA
Accuracy
0.50% Full Scale (standard) F
0.30% Full Scale K
0.30% Reading (unidirectional calibrations only) S
Input/Output & Calibration
±15 VDC input/0-1 VDC bidirectional output B1
±15 VDC input/0-10 VDC bidirectional output B2
±15 VDC input/0-5 VDC bidirectional output B3
+24-32 VDC excitation/4-20 mA bidirectional output B4
+24 VDC input/0-1 VDC bidirectional output B5
+24 VDC input/0-5 VDC bidirectional output B7
±15 VDC input/0-1 VDC unidirectional output U1
±15 VDC input/0-10 VDC unidirectional output U2
±15 VDC input/0-5 VDC unidirectional output U3
+24-32 VDC excitation/4-20 mA unidirectional output U4
+24 VDC input/0-1 VDC unidirectional output U5
+24 VDC input/0-5 VDC unidirectional output U7
Electrical Connector
9-pin D-subminiature (standard) A
Terminal block adaptor, 5-post T
Flying lead adapter, 10 ft (3 m) length L
Mounting
No bracket 0
Mounting bracket, standard 1
Mounting bracket, slotted 2
Trip Relay Settings
Trip A above 50% Full Scale, Trip B above 50% Full Scale* (default setting) AA
Trip A above 50% Full Scale, Trip B below 50% Full Scale* AB
Trip A below 50% Full Scale, Trip B below 50% Full Scale* BB
Trip A below 50% Full Scale, Trip B above 50% Full Scale* BA
*Contact factory for alternate trip relay settings
Description
228A Baratron® 0.2-1000 Torr Differential Capacitance Manometers with 2 Trip Points

228A

Differential Capacitance Manometer, 2 Trip Points, 228A Series

Specifications

  • Type
    Pressure Transducer
  • Sensor Type
    Capacitance Manometer
  • Measurement Type
    Differential
  • Full Scale Pressure Ranges
    0.2, 1, 2, 5, 10, 20, 50, 100, 200, and 1000 Torr and equivalents in kPa, mbar, inches H2O, and cm H2O
  • Analog Output
    0-1 VDC, 0-5 VDC, or 0-10 VDC > 10 kΩ load
  • Fitting Type
    Standard: 1/4 inch OD (6.4 mm) tubes
    Optional: Various
  • Electrical Connector
    15-pin high-density D-subminiature
  • Resolution
    0.01% of Full Scale
  • Accuracy
    0.50% of Full Scale unidirectional or bidirectional standard
    0.30% of Full Scale unidirectional or bidirectional
    0.30% of Reading (unidirectional only) optional
  • Zero Temperature Coefficient
    0.1% Full Scale/°C for standard accuracy specification
  • Span Temperature Coefficient
    0.04% of Reading/°C
  • Sensor Internal Volume
    Measurement Side (Px):1.4 cm
    Reference Side (Pr):9.0 cm
    (when equipped with standard 1/4-inch (6.4 mm) O.D. inlet and reference tubes)
  • Operating Temperature Range
    0° to 50°C
  • Maximum Overpressure
    Measurement Side (Px):120% of Full Scale or 20 psi (140 kPa), whichever is higher
    Reference Side (Pr):120% of Full Scale
  • Maximum Line Pressure
    40 psig (275 kPa)
  • Materials Exposed to Process Gases
    Measurement Side (Px):Inconel
    Reference Side (Pr):Inconel, ceramic, palladium, stainless steel, glass
  • Trip Points
    Two process pressure trip points, independently adjustable from -100% to +100% of Full Scale
  • Trip Relays
    DPDT contacts rated at 1.0 amps at 30 VDC or 0.3 amps at 120 VAC
  • Power Requirements
    ±15VDC (±5%) or +16 to +30VDC @ 75 mA, ripple less than 20 mV
  • Compliance
    CE, SEMI S2

Features

Baratron® Capacitance Manometer Technology

Capacitance manometer sensor schematic showing the internal components

Capacitance manometers are electro-mechanical gauges that can measure both pressure and vacuum. The capacitance gauge translates a pressure-modulated movement in a thin diaphragm into an electrical signal proportional to the pressure. The pressure sensor is the thin diaphragm that is exposed to the pressure or vacuum being measured via the inlet tube. An electrode is mounted in the reference cavity behind the diaphragm. Pressure differences between the process and the reference cavity deflect the diaphragm slightly, changing the distance between it and the electrode. Variations in this distance produce variations in the capacitance between the diaphragm and the electrode creating an electrical signal that is proportional to the pressure change. Since differences in the capacitance signal are produced by physical changes within the manometer and not by changes in the gas properties, pressure measurements by the capacitance manometer are independent of the composition of the gas being measured.

Differential Pressure Measurement

Differential capacitance manometers can be connected to any pressure or vacuum source for use as the reference pressure. These manometers read the difference in pressure between the inlet tube and the reference cavity at the backside of the electrode. Differential pressure transducers can be used to measure either the true differential pressure or vacuum between two locations, or the reference side of the product can be left open to provide a true reference to local atmospheric pressure. Applications include air and gas flow measurements for filters and analytical systems, downstream pressure control in thin film processing systems, and automated leak testing systems.

Inconel® Nickel Alloy Construction

The patented capacitance sensor is built entirely from Inconel® nickel alloys on its measurement side, which offers superior corrosion resistance over long periods of time. Inconel® construction also offers high overpressure tolerances that reduce errors due to line pressure spikes, and high burst pressure ratings that contribute to overall system safety.

Three Analog Outputs

Three (3) different analog output signals (0-1 VDC, 0-5 VDC, and 0-10 VDC) are included for use in nearly any control or data acquisition system.

Twelve Different Fitting Types

These Baratron® differential capacitance manometers can be equipped with any of twelve (12) different fittings on either the measurement or reference sides, including common industrial and semiconductor-industry standards like VCR®, NW-KF, VCO®, and NPT.

Two Independently Adjustable Trip Relays

Two (2) independently-adjustable trip relays are included for control of external equipment and components based on a pressure trip point.  The trip points are adjustable from -100% to +100% of the full-scale measurement range. The DPDT relay contacts are rated at 1.0 amp at 30 VDC or 0.3 amp at 120 VAC.

Accessories

Power Supplies and Displays

Compare Description Drawings, CAD & Specs Avail. Price
pr4000b digital power supply and readoutPR4000BF2V2
$2,982
pr4000b digital power supply and readoutPR4000BF5V2
$2,785
pr4000b digital power supply and readoutPR4000BF2V3
$3,033
pr4000b digital power supply and readoutPR4000BS2V3
$2,729
pr4000b digital power supply and readoutPR4000BS2V2
$2,706
pdr2000a two-channel digital power supply and readoutPDR2000AO
$999
pr4000b digital power supply and readoutPR4000BF5V3
$2,785