Michell Instruments Pura 2-Wire, User Manual

Page: 12 / 36

Pura 2-Wire/3-Wire/Digital Transmitter
User’s Manual
Michell Instruments 5
INSTALLATION
2.5 Preparation of the Transmitter Cable
The transmitter cable is NOT supplied as standard. A cable can be obtained by contacting
your local distributor or Michell Instruments (see www.michell.com for details).
Cable connection to the Pura transmitter is made via the removable connector. Removing
the central screw enables the connector terminal block to be removed from the outer
housing by using a small screwdriver to prise it clear.
i
O-ring
and washer
Figure 5 Connector Terminal Block Removal
Caution: When removing the central screw ensure that the
small sealing O-ring and the washer are retained on the screw
and are present during re-installation.
For the transmitter to work properly, and to achieve maximum performance, the
transmitter cable must be connected to the transmitter connector as shown in the
drawings below:
2-wire
h
h
Supply
4-20 mA
PIN 3
PIN 1
(GND)
Screen/Shield
Optional
Figure 6 Rear of Connector Terminal Block - 2-wire
Always connect the 4-20 mA return signal to a suitable load
before the power is applied. Without this connection the sensor
may be damaged if allowed to operate for prolonged periods.
3
1
Max Load
250R @ 12V
500R @ 24V
Supply
12V Min
28V Max
+
Figure 7 Electrical Connections - 2-wire