MA-005 - Minitrans Installation Manual - Rev 4.5
13-Aug-20
Page 33 of 86
10
ELECTRONICS
10.1
Input Board
The product has an input board and a marshalling board for connections. The input
board is located on the internal bottom tier of the product and has screw terminals to
provide connections to the alarms, PSTN, serial communications and transformer load
sensor (see Appendix I).
Communications modules are found on the marshalling board located on the second tier
of the product (behind the plastic cover). All cabling, communications and sensor wiring
that lead into or out of the product are made through the two 16 mm cable glands on the
bottom of the product. There are also cable tie bases on the inner side of the front panel
for securing the cables.
After the product has been in operation, components may get hot within the
inner compartments and inside the front panel. Care should be taken that all
items have cooled sufficiently before carrying out any work.
10.2
Alarm Connections
The product has two relays
—
a service relay and a caution and alarm relay
—
and two
corresponding external sunlight-visible red and green LEDs on the front door. When the
product is connected to the mains power and is powered on, the green LED illuminates
continuously. Relay outputs are located along the terminal strip on the Input board (see
Appendix I). Three connections are provided for each relay: NO (Normally Open), NC
(Normally Closed), and COM (Common). The relays can handle a maximum of 1 A 250 V
AC, 300 mA 110 V DC or 1 A 30 V DC (see Appendix I).
▪
Relay 1 is the service relay.
The green LED flashes if internal error checking detects an error condition. If after the
next measurement run, there are no error conditions present, the green LED resumes
continuous illumination.
▪
Relay 2 is the caution and alarm relay.
The red LED indicates when a user-configurable caution and/or alarm threshold is
reached. Flashing denotes a caution state whereas continuous illumination denotes
an alarm state. If after the next measurement run, no caution or alarm states exist,
the red LED switches off. Use the TransConnect software to set alarm and caution
limits for many different combinations of results. (See the TransConnect User Guide
for more information).
10.3
Accessory Power
There are additional power points to c12 V DC or +24 V DC at 0.5 A accessories,
such as wireless modems or protocol converters. These are available on the Input board
at the front of the product as shown in Figure 10-1).