Ground
A good common ground reference (earth ground) is essential for proper operation of
the AL250-V2. A good earth ground or power circuit ground should be connected to
the ground terminal block l on the enclosure backpanel.
Connections
Screw terminals are provided for making connections for sensor inputs and power.
Sensor and I/O terminals are located on the inside of the door of the AL250-V2
enclosure. The terminals are numbered in ascending order from left to right. Power
terminals are on the backpanel of the enclosure. Power should always be
disconnected from the AL250-V2 before making or changing any connections on
these terminals.
Power
The incoming power is connected on the terminal blocks just below the transformer
on the backpanel of the enclosure. The triple tap transformer will accept 115, 208, or
230 volts AC (50 or 60 Hz). Depending upon the voltage being used, the power is
connected to one of three terminals as illustrated.
If 460 VAC is the only power source available,
use a separate step-down transformer to lower
the voltage to 230 VAC.
The AL250-V2 transformer is equipped with an
internal thermal fuse on the primary winding to
prevent damage from overloads.
Always replace the terminal block cover after
making the power connection.
Verify line voltage and check primary wiring
(diagram at right) before applying power to
the AL250-V2. Primary voltages outside of
the ranges shown at right will result in
damage to the AL250-V2 circuitry.
In locations subject to transient power
surges, use a surge protector on the primary
connections to the transformer. See
Appendix B for more information on surge
protection.
2-2
34
33
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
10
09
08
07
06
05
04
03
02
01
14
13
12
11
37
36
35
Terminal Blocks for I/O
and Sensor Connections
Terminal Blocks for
Power Connections
!
!
0
VA
C
11
5
VA
C
20
8
VA
C
23
0
VA
C
C
on
ne
ct
A
C
N
eu
tr
al
H
er
e
If
11
5
VA
C
, (
10
8-
13
0
VA
C
)
C
on
ne
ct
H
er
e
If
20
8
VA
C
, (
18
7-
23
0
VA
C
)
C
on
ne
ct
H
er
e
If
23
0
VA
C
(
21
6-
25
4
VA
C
),
C
on
ne
ct
H
er
e
C
on
ne
ct
G
ro
un
d
H
er
e
0
11
5
20
8
23
0
