ACM20 Series
Four-Function AC Power Meters
PANEL INSTALLATION
All connections to ACM20 power meters must be made after the unit
is securely attached to the panel and with all associated load and
supply voltages de energized (off), using extreme caution and observ-
ing all safety measures applicable to the user’s installation.
Care should be exercised when passing conductors through the
power meter’s built-in current transformer L1. The installed wire-
positions should be such that minimal mechanical forces are applied
to current transformer L1, TB1, or to the ACM20 power meter itself.
In high-vibration environments, it is strongly recommended that
adequate strain reliefs be used for all wiring.
Using Figure 5 as a guide, carefully insert the ACM20 assembly into
the panel opening. From the rear of the panel, install and then tighten
the four #2-56 hex nuts over the threaded studs.
Tighten each nut to
15 to 20 ozf-in (0.106 to 0.140 N-m).
Use only the factory-supplied
hardware as the use of substitute hardware could result in an unsafe
installation and/or adversely affect the reliability of the installation.
The recommended range of panel thickness that can be used with the
supplied hardware is 0.040 inches (1.0mm) to 0.25 inches (6.4mm).
Panel thicknesses outside of this range may require additional user-
supplied hardware or modifications. Front panel space permitting,
ACM20 power meters will fit most existing ACA-20RM / ACA-20PC
ammeter cutouts, allowing for easy upgrading of existing installations.
PANEL
ACM20
2-56 Hex Nuts (4 places)
Tighten each nut to 15 to 20 ozf-in (0.106 to 0.140 N-m).
Panel Cutout
L1
SIDE VIEW
Figure 5. Panel Installation
PANEL CUTOUT
RECOMMENDED DRILL AND PANEL CUTOUT DIMENSIONS
INTERNAL CORNER RADII:
0.032 (0.81) MAX.
1.07
(27.18)
0.838* - 0.870
(21.29* - 22.10)
1.336* - 1.426
(33.93* - 36.22)
1.626 (41.30)
0.093 (2.362) DIAMETER (4 REQUIRED)
* The two dimensions marked with an * specify the
minimum recommended panel cutout opening for
ACM20 power meters. Space permitting, the larger
dimensions noted (0.87in., and 1.426in.) should be
used. The panel opening must be centered vertically
and horizontally between the four 0.093 (2.362mm)
diameter holes.
www.murata-ps.com/dpm
email: sales@murata-ps.com
03 Mar 2011 MPM_ACM20 Series.A09
Page 5 of 6
MURATA [ MURATA MANUFACTURING CO., LTD. ]
