Setra System Model 595 - Manual (Page 3)

1.0 Introduction
Model 595 is a level measuring transducer for precise measurements of ground
and surface water levels. The transducer measures pressure and temperature
signals and, by compensating these measured values for temperature effects, the
relative density of water and the specific gravity in the users location, provide a
highly accurate and repeatable “true” level measurement. The resultant level is
available either as an analogue output or as a digital output
2.0 Safety Instructions
Important Note: Setra’s Model 595 pressure transducer is designed and manufac-
tured in accordance with Sound Engineering Practice as defined by the Pressure
Equipment Directive 97/23/EC. Pressure transducer products designed to meet
the highest risk category “IV” of the Pressure Equipment directive are clearly
marked on the label by “CE0086”. Compliance is achieved through modules “B&D”.
No other products should be used as “Safety Accessories” as defined by the PED,
Article 1, Paragraph 2.1.3.
EMC: Model 595 conforms with the essential protection requirements of the EMC
Directive 89/336/EEC amended by certified type testing to EN 61000-6-3 and
EN61000-6-2. Conformity with the requirements of the CE mark only applies
when the installation conditions described in these instructions have been met.
3.0 Hazardous Products
The 595 may be classified as Electrical, Electro-Mechanical and Electronic equip-
ment.
These products are tested and supplied in accordance with our published
specifications or individual special requirements that are agreed in writing at time
of order. They are constructed so as not to affect adversely the safety of persons
and property when properly installed, maintained and used by qualified person-
nel, in the applications for which they were designed and manufactured. Refer to
installation and maintenance instructions for further details.
4.0 GENERAL
● Transducer should not be subjected to greater than maximum allowable
pressure range as defined on the transducer label.
● Transducer should not be subjected to mechanical impact.
● The effects of decomposition of unstable fluids should be considered by the
user when placing this device in service.
● Pressure range must be compatible with the maximum level being mea-
sured.
● Pressure media must be compatible with the transducer wetted parts which
are:
UNS31803 Stainless Steel, BS En 10088-3:1995 No. 1.4462.
Polyurethane
Acetal
Nitrile
8.3 Cleaning
Inspection and cleaning of the product is recommended as part of a
preventative maintenance procedure. The required inspection period will depend
on the nature of the application environment. To inspect the product unscrew
the nose cover. Figure 2, and view the sensor diaphragm. The housing should be
free from deposits. Cleaning with a cotton bud (Q-TIP) is possible, but extreme
care must be taken not to deform the sensor diaphragm during cleaning.
Figure 2
Inspecting and Cleaning the Sensor
9. Advanced Operation
The 595 allows for a number of advanced operations not normally
available.
Re-Range 4 to 20mA Output
Often users wish to measure a specific water level that is not the same as the full
range output of the transducer. For example, if the sensor output was 10MH
2
O
and the user wishes to measure up to 4mH
2
O then without a down range feature
the output for the 10mH
2
O unit in the users applications would be 0 to 40% of
the range or 4 to 10.4mA. In this situation it is possible to use the SDI12 interface
to program calibration coefficients into the sensor to provide 4 to 20 mA for the 0
to 4mH
2
O application, with the 10mH
2
O sensor.