Conductor Sizing And Routing; Upstream Overcurrent Protection Device - ABB OVRHSP Series Installation, Operation And Maintenance Manual

Conductor sizing and routing

CAUTION:
The OVRHSP(SR) series unit's performance will be limited
severely if the conductors are (a) too long, (b) are of too
small a wire gauge, (c) have too many bends or (d) have
sharp bends. For optimum performance never exceed
3.048 meters (10 ft.) conductor lengths.
The factors listed above should be addressed during the
design of an installation to reserve a suitable place for the
OVRHSP(SR) series unit next to its point of connection to the
electrical system. The selected mounting location should allow
for the shortest possible conductor runs and a direct route
with a minimum of bends. If bends are required, they should be
sweeping bends. Do not make sharp 90° bends for appearance
purposes because they will severely decrease the effectiveness
of OVRHSP(SR) series unit.
Binding or twisting conductors together using tie-wraps or
electrical tape increases the protection performance of the
device.
The conductor length should be as short as possible to ensure
the maximum level of protection. Wires are marked with
(Phase A, B, C, Line 1, Line 2, Neutral or Ground) depending
on the model.

Upstream overcurrent protection device

The OVRHSP(SR) series unit is a Type 1 SPD which is
suitable for use in both Type 1 and Type 2 SPD applications.
The OVRHSP(SR) series unit is a one-port SPD and is to be
connected in parallel with the electrical system. It may be
connected via a circuit breaker, molded case switch, fused
switch, or connected directly to the bus of the panelboard or
switchboard it is protecting. If direct bus connection is used,
ABB recommends installing the OVRHSP(SR) series unit behind
a disconnect switch or other disconnecting means for ease of
serviceability.
If the SPD is connected to a dedicated OCPD, a 60A breaker is
recommended (30A minimum, 200A maximum).
6 Product manual | OVRHSP/OVRHSR surge protective device
Conductor sizing and routing (OVRHSP)
ABB recommends installing the OVRHSP unit by following
conductor size for phase, ground and neutral connections. The
conductor length should be as short as possible to ensure the
maximum level of protection.
Table 2: Maximum recommended conductor size
OVRHSP models
OVRHSP120
OVRHSP160
OVRHSP200
OVRHSP240
OVRHSP300
OVRHSP400
– 60 through 100kA units and all OVRHSR units are furnished
with #10 AWG leads. Leads should be shortened during
installation in order to minimize conductor length.
– 120 through 400kA units are shipped with compression box
lugs. The set screws on the box lugs should be torqued to
2.3 Nm (20 in-lbs.).
– Terminals are identified with markers (Phase A, B, C, Line 1,
Line 2, Neutral or Ground)
Conductor size
#6 AWG
#6 AWG
#4 AWG
#4 AWG
#4 AWG
#4 AWG