3.6 EMC Certification
This product complies with EN61326 Electrical Equipment for Measurement Control and Laboratory
use – EMC Requirements for Minimum Requirements and Industrial Locations. Special caution should
be taken to meet Standard EN61000-4-5: 1995 Surge Immunity if any of the following conditions apply
to the installation: the product is installed outside; all or any part of the cable is exposed to the outside;
the cable is greater than 30 meters in length. In order to meet the CE Surge Immunity requirements, the
following conditions must be followed during installation:
1.
Shielded cable must be used, and the shield must be tied to earth ground (not power supply
ground) on at least one end of the cable shield/drain wire. The shield must be maintained all
the way from sensor to the power supply.
2.
If unshielded cable is used, an earth grounded metal conduit should be used to replace the
shielded cable.
3.
For a sensor with a metal body or enclosure, the body/enclosure must be grounded to earth.
4.
If a protective metal housing is used, the housing must be able to withstand at least 2 kV from
the housing to earth ground without damaging the circuit.
4.0 CALIBRATION
The 267 and 267MR transducer is factory calibrated and should require no field adjustment. Generally, the
mounting position will have a zero shift effect on ranges below 1” WC. Whenever possible, any zero and/or
span offsets should be corrected by software adjustment in the user’s control system. However, both zero
and span adjustments are accessible under the cover of the unit, below and to the right of the terminal strip.
The 267 and 267MR transducer is calibrated in the vertical position at the factory (mounting tabs vertical).
4.1 Voltage Output Zero Adjustment
While monitoring the voltage between the positive output (+SIG) and common (GND), and with both
pressure ports open to atmosphere, the zero may be adjusted by turning the zero adjustment screw. (See
Diagram 1 for location of zero adjustment.) Factory settings are:
Unidirectional Pressure Ranges
Bidirectional Pressure Ranges
Zero Adjustment
Output
Zero Adjustment
Output
0.05 VDC (
±
25 V)
0-5 VDC
2.5 VDC (
±
25 mV)
0-5 VDC
0.05 VDC (
±
50 V)
0-10 VDC
5 VDC (
±
50 mV)
0-10 VDC
4.2 Voltage Output Zero Adjustment
(Complete the zero adjustment setting before setting span.)
Span of full scale output adjustments should only be performed by using an accurate pressure standard
(electronic manometer, digital pressure gauge, etc.), with at least comparable accuracy to the 267 or
267MR transducer (<±1% FS). With full range pressure applied to the high pressure port (reference port
open to atmosphere), the span may be adjusted by turning the Span adjustment screw. (See Diagram 1
for location of Span adjustment.) Factory settings are:
Unidirectional Pressure Ranges
Bidirectional Pressure Ranges
Span Adjustment
Output
Zero Adjustment
Output
5.0 VDC (
±
25 V)
0-5 VDC
2.5 VDC (
±
25 mV)
0-5 VDC
10 VDC (
±
50 V)
0-10 VDC
5 VDC (
±
50 mV)
0-10 VDC
Example 1: Unidirectional pressure range of 0 to 1” W.C. with 0 to 5 VDC output
Apply 1.00” W.C., adjust span to 5 VDC (—25 mV)
Example 2: Bidirectional pressure range of ±5” W.C. with 0 to 5 VDC output
Apply 5.00” W.C., adjust span to 5 VDC (±25 mV)
