Siemens Surge Protective Device TPS3 12 - Manual (Page 8)

Table 2: Weight & Dimensions
TPS3 12 H/W/D (in./mm.) Weight
Standard Enclosure
12" x12" x 7.5"
(305x305x191) 22 lbs
(10 kg)
Standard Enclosure, 400 – 500kA with Opt.
Disc. Switch 16" x 14" x 6"
(496x356x152) 32 lbs
(14.5 kg)
4X Non-Metallic
14" x 12" x 7"
(356x305x178) 14 lbs
(6.4 kg)
4X Non-Metallic, 400 – 500kA with Opt.
Disc. Switch 16" x 14" x 7"
(496x356x178) 21 lbs
(9.5 kg)
4X Stainless
12" x 12" x 7"
(305x305x178) 24 lbs
(10.9 kg)
4X Stainless, 400 – 500kA with Opt. Disc.
Switch 16" x 14" x 6"
(496x356x152) 33 lbs
(15 kg)
Pullbox & Flush mount
12" x 12" x 6”
(305x305x152) 21 lbs
(9.5 kg)
Pullbox & Flush mount, 400 – 500kA with
Opt. Disc. Switch 16" x 14" x 6"
(496x356x152 29 lbs
(13.2 kg)
TPS3 15
Internal disconnect switch standard
Standard Enclosure
20" x 20" x 7.5"
(508x508x191) 52 lbs
(23.6 kg)
4X Non-Metallic
24" x 24" x 8"
(610x610x203) 52 lbs
(23.6 kg)
4X Stainless
20" x 20" x 7"
(508x508x178) 53 lbs
(24 kg)
Pullbox & Flush mount
20" x 20" x 6"
(508x508x152) 53 lbs
(24 kg)
Service Clearance
Service clearance is needed at the front of the unit; 36 inches minimum
is the required distance for clearance pursuant to the NEC
® .
Lead Lengths & Maximizing SPD Performance
SPDs 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: 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.
Tip: 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.
Shortest Leads Possible
• Leads must be as short and straight as possible - See NEC Art.
285.12
• No long leads
• No sharp bends
• No wire nuts
• How short is short enough? As short as you can make it.
• How long is too long? If anyone else can make it shorter.
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.
Voltage Rating
Before installing SPD, verify that it has the same voltage rating as
the power distribution system. Compare the SPDs nameplate voltage
or model number and ensure that SPD configuration matches the
intended power source. See Table 1.
The specifier or the user of the device should be familiar with the
configuration and arrangement of the power distribution system in
which any SPD is to be installed. The system configuration of any
power distribution system is based strictly on how the secondary
windings of the transformer supplying the service entrance main or
load are configured. This includes whether or not the transformer
windings are referenced to earth via a grounding conductor. The system
configuration is not based on how any specific load or equipment is
connected to a particular power distribution system.
480V System Example: SPDs should be installed per the electrical
system, not per a load or motor’s wiring connection. For example, a
480V three phase motor might appear to be connected as a 480V Delta.
In actuality, the serving distribution system might be a 480Y/277V
grounded Wye, with or without a neutral pulled to the motor or MCC.
The system is still a 480Y/277V Wye, even though the load is connected
as a Delta. A grounded Wye has a defined reference to ground (i.e.,
neutral is bonded to ground). Some Delta systems are ungrounded,
which have no reference to ground and are known to become unstable
in certain situations. Such instability can cause line to ground voltage
fluctuations that may prematurely fail SPDs. For this reason, the NEC
Article 285 has placed SPD restrictions on ungrounded systems. As
generalizations, SPDs for ungrounded systems can be installed on
grounded systems with a clamping performance penalty. However,
SPDs for grounded systems installed on ungrounded systems are
almost certainly destined for premature failure. Contact Tech Support
at 1.888.333.3545 for further information.
Circuit Breaker and Disconnect Switch
The TPS3 12 and TPS3 15 family SPDs are tested and qualified as a
Type 1 SPD per UL 1449 Third Edition and 2008 NEC. This SPD can be
installed on the line side of the service overcurrent device per 2008
NEC Article 285. As a generalization, it is more practical to install on
load side of main overcurrent device for maintenance reasons.
When connected on load side of main disconnect, a 60A circuit breaker
is recommended. The circuit breaker is the intended disconnect
switch and provides short circuit protection to the connecting
conductors. These SPDs have internal overload protection elements
within the product. A breaker or disconnect is not required for the
SPD’s overcurrent protection. These SPDs have demonstrated 200kA
Short Circuit Current Ratings (SCCRs). 120V & 120/240V models have
demonstrated 100kA SCCRs. Refer to label on unit.
5