6 | 18
4 Termianl Assignment
The electrical connections are made via screw-clamps. The numbering can be found on the front side
of the amplifier. The maximum wire cross section is 2,5 mm². Maximum interference immunity is
achieved by direct connection of the cable screen with “clean” and low resistance protective ground
(PG). A lengthening of the cable screen makes the interference immunity considerably worse. The
connection of the screen should be done directly with a cable clamp. If, however, a connection to a PG
is not possible, the cable screen may be connected to clamp 30 of the amplifier (analogue
ground/screen). Anyhow, enough interference immunity is to be ensured.
Terminals “supply ground” and “analogue ground” are isolated galvanically. To unset this isolation
clamp 3 and 4 are to be bridged.
4.1 Supply voltage
The supply voltage is with version -24E in the range of 18 to 30 VDC and with version –E12 within 10
to 18 VDC. The presence of the supply/ internal operating voltage is indicated by the 2 green LEDs on
the front.
To protect the electronics an (to the supply voltage version corresponding) internal self-healing
“polyswitch-resettable®” fuse is built in. Whether an external additional fuse is necessary is to be
checked. However, an additional external delay fuse of 0,5 A is recommended.
If the indicator LEDs go off, the supply voltage and possibly existing external protection has to be
checked.
Notice:
While switch-on the amplifier it is capacitive. Thus, the switch-on current is greater than the
operating current. This must be taken into consideration when dimensioning and selecting the power
pack, especially if several amplifiers are being wired to the same power source.
PIN
Description
PIN
Description
1
Operating voltage
16
GND analogue output/Screen
2
GND Operating voltage
17
+ Signal Strain Gauge Transducer Channel 1
3
GND Operating voltage
18
- Signal Strain Gauge Transducer Channel 1
galvanic isolation
19
+ Strain gauge excitation voltage Transducer Channel 1
4
GND analogue output
20
+ Strain gauge excitation voltage Transducer Channel 2
5
n.c.
21
+ Strain gauge excitation voltage Transducer
6
n.c.
22
+ Sense
7
n.c.
23
GND analogue output
8
GND analogue output
24
- Strain gauge excitation voltage Transducer Channel 1
9
Analogue output channel-2 4…20 mA (Ver.-420-
)
25
- Strain gauge excitation voltage Transducer Channel 2
10
GND analogue output
26
- Strain gauge excitation voltage Transducer
11
Analogue output channel-2 0…10 V
27
- Sense
12
GND analogue output
28
+ Signal Strain Gauge Transducer Channel 2
13
Analogue output channel-1 4…20 mA (Ver.-420-
)
29
- Signal Strain Gauge Transducer Channel 2
14
GND analogue output
30
GND analogue output/Screen
15
Analogue output channel-1 0…10 V
