Cosa-xentaur Xentaur LPDT Manuel d'utilisateur télécharger pdf (Page 23)

LPDT User’s Manual

page 16

LPDT (the tension washer should be compressed), so that it

does not come loose during use.

3.3.2 Electrical Installation

The LPDT will operate properly with 10VDC to 33VDC at

its input, if this voltage is exceeded the internal fuse may

blow. When selecting the power supply voltage do not

neglect the drop across any current measurement resistor

and wiring in the loop. The connector is a standard 2.1mm x

5.5mm (12mm minimum barrel length) DC power jack, an

internal diode bridge accommodates either polarity. The

LPDT may be powered using an off-the-shelf wall trans-

former with 2.1mm connector, or from a power supply

using the provided connectorized cable. The provided cable

is terminated with a connector which has a retainer, the

retainer may be used to secure the connector to the LPDT

thus avoiding accidental disconnection.

The LPDT will draw 4mA to 20mA from the power supply

depending on the dewpoint being measured. The dewpoints

corresponding to 4mA and to 20mA are user selectable, in

between the current will vary linearly to the selected engi-

neering units, see appendix G.

Various strategies for interfacing with the LPDT are shown

in Appendix D.

Please observe good electrical safety and grounding prac-

tices when connecting any electrical equipment; connecting

one end (e.g. negative) of the power supply to earth ground

is advisable.

After the installation is complete, proper detection by the

user’s equipment of the 4-20mA output, may be tested using

the Analog Output test feature of the LPDT, see section

3.4.5.6.

1 2 ... 18 19 20 21 22 23 24 25 26 27 28 ... 53 54

Pas de commentaire

Cosa-xentaur Xentaur LPDT Manuel d'utilisateur Page 23