Filter
Top Products
Figure 1. Typical Parallel Connections
NOTE: Safety Ground required for ALL units.
Page 4
Table 2: Voltage Rating and Service Type (by Model)
Terminals
Terminals have been provided inside the APC modular SPD units for the line (phase), neutral, and equipment safety ground
connections. Terminal wire size for all models is #8 AWG - #1 AWG. Installation torque is 65 inch-pounds.
System Grounding
An equipment grounding conductor must be used on all electrical circuits connected to the SPD. This requirement is
primarily for safety, although SPD performance is enhanced by proper grounding. Proper operation of any surge suppression
system or device depends on a proper grounding system. Incorrect grounding practices will reduce the effectiveness or
interfere with SPD system operation and performance, as well as endanger personnel and equipment. For the best perfor-
mance, use a single point ground system where the service entrance grounding electrode system is connected to and bonded
to all other available electrodes, building steel, metal water pipes, driven rods, etc. For sensitive electronics and computer
systems, it is recommended that the ground impedance measurement be 25 ohms or less. When metallic raceway is used as
an additional grounding conductor, an insulated grounding conductor should be run inside the raceway. Adequate electrical
continuity must be maintained at all raceway connections. Do not use isolating bushings to interrupt a metallic raceway run.
A separate isolated ground for the SPD is NOT recommended. Proper equipment connections to grounding system and
ground grid continuity should be verified via inspections and testing on a regular basis as part of a comprehensive electrical
maintenance program.
Parallel Connection
When making a parallel type of connection (Figure 2), the length of the wiring to the Surge Protective Device (SPD) must be
kept as short as possible to substantially enhance the performance. Long wire runs are to be avoided for the unit to perform
as intended.
To reduce the impedance the wire displays to surge currents, the phase, neutral (if used), and ground conductors are to be
routed within the same conduit and should be tightly bundled or twisted together to optimize the performance of the unit.
Sharp bends in the conductors are to be avoided.
rebmuNledoMepyTecivreSdnagnitaRegatloV
D4PMPdna,4PMP,D3PMP,3PMP esahPelgniS,stloV042/021
D4FMPdna,4FMP,S3FMP,D3FMP,3FMP eriW5,EYW,esahP-3,stloV802/021
SD4GMPdna,S4GMP,D4GMP,4GMP,D3GMP,3GMP eriW5,EYW,esahP-3,stloV084/772
SD4LMPdna,Y4LMP,S4LMP,D4LMP,4LMP,S3LMP,D3LMP,3LMP eriW5,EYW,esahP-3,stloV006/743
On 4-Wire Power Systems, neutral to ground bonding should be
installed per the NEC. Failure to do so could cause equipment damage.