48
PLM Series Operation Manual
Pin 1: Ground/shield
Pin 2: Hot (+)
Pin 3: Cold (-)
Figure 10-2
When paralleling analog inputs of several
PLMs, either by using the Link connectors
or an external paralleling system, bear in
mind that the drive capability of the source’s
output stage (typically a mixing console) may be
limited. As a general rule, it is inadvisable to attempt
to parallel more than four PLM inputs together in this
way. (Two inputs on the same PLM do count as two!)
If it is necessary to drive a greater number, the use
of a good quality balanced audio line driver or
distribution amplifier is recommended.
10.2.1.1 Unbalanced operation
Balanced interconnections are recommended
whenever possible. However, if it is necessary to
drive the PLM from equipment with an unbalanced
output, wire the inputs as shown in the diagram
below:
1
2
3
COLD
HOT
SCRN
COLD
HOT
SCRN
Unbalanced Output
(Typically phono)
Balanced Input
(XLR)
Figure 10-3
This method still uses twin-and-screen (‘balanced’)
cable and standard XLR pin connections at the
PLM end, but the ‘cold’ wire and the cable screen
are connected together to the signal ground of the
equipment at the source end.
This usually provides better noise and hum rejection
than the more common method of joining pins 1 and
3 together in the XLR. However, if only a single-
core (“unbalanced”) cable is available, the following
method may be employed. See figure 10-4.
10 bACK PANEL INTERFACE
10.1 Power inlet
A Neutrik NAC3 Series PowerCon connector rated
at 32 A is fitted to the rear of the PLM for AC mains
input. The power cable (AC cord) supplied with the
PLM has the mating connector ready-fitted, but may
require a mains (AC) plug specific to your country
to be fitted to the other end. See section 5.5 for
wiring details.
10.1.1 PowerCon wiring details
If it is necessary to rewire the PowerCon connector,
or to make custom power cables for your particular
installation, please observe the following connection
details:
PowerCon Pin
230 V Version
115 V Version
L
brown
black
N
blue
White
Green/Yellow
Green
Table 10-1
10.2 Audio Input and Links
10.2.1 Analog inputs and Links
INPUT
1
INPUT 2
LINK
1
LINK 2
PIN 1: SCRN 2: POS 3: NEG
ANALOG WITH
I
SO-
F
LOAT
TM
Figure 10-1
The electronically-balanced analog inputs are on
XLR3F connectors. The Link outputs on XLR3M
connectors are directly paralleled to the inputs. All
XLRs are wired to IEC268 as follows in figure 10-2:
