Advanced Protection XGA User Manual
Page 3
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3
PRE-INSTALLATION & INSTALLATION PLANNING
Operating Environment
The standard unit is in a Type 1 enclosure. Other enclosure
types are available as options. Before installing, ensure
that your enclosure type and application are appropriate
per NEMA 250 with regard to moisture, dirt, excessive dust,
flammable materials or atmospheres, corrosive vapors, etc.
This SPD is designed in an ambient temperature range of -40°C
(-40°F) to +60°C (+140°F) with a relative humidity of 0% to 95%
(non-condensing). Excessive temperature may inadvertently
operate internal thermal overtemperature protectors.
Audible Noise
SPD background noise is negligible or non-existent, and
does not restrict the location of installation.
Mounting, Dimensions, and Weight
This SPD is designed to be wall mounted. The standard
enclosure is: 12” x 12” x 6” (L/W/D), and the weight is
25 lbs. The XTE Series is designed for internal mounting
in the electrical distribution equipment. Standard backplane
size is: 10.75” x 10.88” x 4.5”, and the weight is 15 lbs.
Service Clearance
Service clearance is needed at the front of the TE Series
unit only, 36 inches minimum is the required distance for
clearance pursuant to the NEC
®
.
Maximizing SPD Performance
SPD’s must be located as close to the circuit as possible
to minimize parasitic losses. Surges are high current, high
frequency events that cause substantial voltage drops across
conductors. This hurts SPD performance. Use the shortest &
straightest possible leads. Pre-Plan installations and ensure
that nearest breaker positions are used. If new construction,
adjust breaker locations as appropriate.
Tip: Voltage drops for normal 120V or 277V lines might be 2-3V per
hundred feet. In surge applications, voltage drops might be 100-150V
per foot. These voltage drops add to clamping voltage, thus hurting
performance. Make every effort to keep leads short and straight.
As distribution gear becomes larger, shorter leads are more
difficult to accomplish. When longer leads are unavoidable,
gently twist leads together (one to two twists per foot), or tie-
wrap leads together.
Tip: surges create magnetic fields per the ‘right-hand rule’. When current
goes in direction of thumb, magnetic field is in direction of curl of fingers.
As surge current goes to SPD, fields are created in one direction. When
the SPD sends those currents to neutral and/or ground, current goes
in the opposite direction. If ‘coming & going’ are on the same axis, the
magnetic fields can be cancelled, thus avoiding performance decrease.
Gentle twists, bundling & tie-wraps accomplish this.
Cascade Surge Protection
For optimum surge protection, cascade or staged surge
suppression should be implemented at the service entrance
and downstream locations as appropriate. Known or expected
surge sources, as well as sensitive loads, should also have
localized surge suppression. For interconnected electronic
loads (data cabling), SPDs should also be utilized to protect
the devices on either end of the interconnecting data cables.
Overcurrent Protection
SPDs draw very little current under normal conditions and
conduct for a brief duration upon encountering a transient
surge current. This SPD contain internal overcurrent and
overtemperature protection to protect against abnormal
voltage conditions.
Supplemental overcurrent protection is not required to protect
this SPD. However, connecting conductors require protection
in Type 2 or 4 applications. Follow applicable codes.
Circuit Breaker and Disconnect Switch
This XGA family SPD is tested and qualified as a Type 2 SPD
per UL 1449 Third Edition and 2008 NEC
®
. This SPD can be
installed on the load side of the service overcurrent device per
2008 NEC
®
Article 285.
When connected on load side of main disconnect, we suggest
connecting via a 60A circuit breaker. The circuit breaker is the
intended disconnect switch and provides short circuit protection
to the connecting conductors. The XGA Series has internal
overload protection elements within the product. A breaker or
disconnect is not required for the SPD’s overcurrent protection.
XGA SPD’s have demonstrated 200kA Short Circuit Current
Ratings (SCCR). Confer to label on unit.
Wire Size and Installation Torque
This is a parallel-connected SPD; it is not series-connected.
The size of the SPD wiring is independent of the ampere
rating of the protected circuit. Recommended wire is 6
AWG for phase, neutral and ground connections. Torque
connections to 18 inch-pounds. Conductor length should
be as short as possible.
If other wire sizes are used, we recommend that all
conductors be the same gauge. Note that larger conductor
might appear to be beneficial; however, it tends to have
the same inductance as smaller conductor and is more
difficult to work with.
Terminals accept 14 - 2 AWG conductor with 6 AWG being
preferred. Coordinate conductor size and overcurrent
Special Enclosure Considerations
Removing and Reconnecting the Ribbon Cables
The ribbon cables are marked with matching phase
connections. If any of the cables are removed, reconnect
the cables as marked.
NEMA Type 4X Enclosure
On rare occasions in high temperature climates, XGA’s
inside clear-cover polycarbonate enclosures have
experienced internal temperatures exceeding 200°F.
This inadvertently operates the overtemperature safety
disconnectors inside the SPD. We recommend positioning
the unit so that the clear front avoids direct summer sunlight
by shading or not facing west.
The NEMA Type 4X enclosure is shipped with its mounting
brackets and installation screws packaged inside it. Use
the enclosed 1/4-20 x 1/2 in. slotted screws to secure the
brackets to the enclosure before installing the XGA SPD
device. Torque these screws to a maximum of 50lb-in.
(6N·m). When installing the cover for the NEMA Type
4X enclosure, torque the cover screws to a maximum of
25lbs-in. (3 N·m).
Flush Mount Option
Remove the display panel and barrier before making any
electrical connections. Replace the barrier and display panel
before energizing the device.