Status Instruments DM4000U, Manual

Page: 17 / 94

3.4 WIRING THE OUTPUT OPTIONS
This section applies to optional outputs fitted to the instrument. There are four types
of output option available; Change-Over Relay, Dual Relay, Current Retransmission
and Programmable voltage Output. These options may be fitted to either slot in any
combination.
There is, however, a restriction when using Programable Voltage Output with the
Current Retransmission card or another Voltage Output. The combined maximum
current should not exceed 50mA; the supply capacity of the Output options. Another
consideration with a pair of analogue output options ( Voltage or Current ) is that
although there is 500V * isolation from the Input, there is no isolation between output
slots.
* See safety information on page 8
3.4.1 RELAY OUTPUTS, option 1 and 2
There are two types of relay outputs available, Dual relay and Change-Over relay. The
dual relay board has two
independent contacts sharing the same common . The
Change-over relay has a single contact with a Normally Open and Normally Closed
output available. The power-off state of the Dual Relay is normally closed, but may
be changed, if required, by modifying hardware links on the board.
It is recommended that a proprietary suppressor network is fitted as close as possible
to the inductive load. DC inductive loads should also have a reverse biased diode
connected as shown.
RELAY OUTPUT
INSTALLATION
Page 17