Dry Contact Option
Two sets of Form C dry contacts are included with the Dry Contact
option. Dry Contacts change state during inoperative conditions,
including loss of power. Any status change can be monitored elsewhere
via Dry Contacts.
A Terminal Block includes two sets of Normally Open (N.O.) and
Normally Closed (N.C) contacts. Both sets of contacts operate the
same. This is shown in Figure 10.
A typical application using a Normally Closed configuration would
connect to one set of the N.C. and Common terminals. During an
inoperative condition, the SPDs dry contact would change state
from Normally Closed to open. The Normally Closed configuration
is recommended because it will detect a wiring defect, such as cut
wire(s), where N.O. will not.
Please note: Dry Contacts are designed for low voltage or control
signals only.
•
Maximum switching current is 5A
•
Maximum switching voltage is 240V DC or AC.
•
Higher energy applications require additional relay implementation
outside the SPD.
An optional Remote Monitor accessory is available to provide visual
and audible status. The Remote Monitor will consume one of the two
sets of Dry Contacts.
Remote Monitor Accessory
A Remote Monitor—Model No. RMSIE (ordered separately) is available
for remote annunciation. It requires a standalone 120V power source
(wall plug transformer) and uses one set of Form C dry contacts.
The Remote Monitor can be configured to monitor several SPDs
simultaneously. Installation is detailed in a separate document. Contact
factory as appropriate.
Figure 10: Dry Contact Connection Configuration
NO
DRY CONTACTS
NC NC C NO
C
Maintenance
SPDs require minimal maintenance. Periodic inspection of diagnostic
LED indicators ensures proper operation. Clean SPD as appropriate.
Troubleshooting & Service
Please contact TPS Technical Support at 1.888.333.3545 for service
related issues.
Quality SPDs are designed and tested to withstand severe duty.
However, there are various electrical anomalies against which
SPDs cannot protect. These are generally Sustained Overvoltages
also known as Temporary Overvoltages (TOVs). In this context,
Sustained Overvoltages may be only a few cycles. Failed SPDs tend
to be symptoms, not root causes. There may be larger issues at play.
Regardless of cause, SPDs attempt to protect their load until failure.
Bonding or reference to ground problems are the root cause of
many SPD problems. If the SPD shows problems on startup, there
is reasonable chance of bonding/grounding/misapplication issue.
Such problems permanently damage the SPD. If not corrected, SPD
problems will reoccur.
Tip: Visually confirm N-G bonding. Be aware that a voltmeter
measuring N-G can be misleading. For example, N-G voltage
could read 0V because neutral and ground are at the same
potential purely by happenstance, not because they are
bonded. Visually confirm bonding.
Tip: Experience indicates that regulation-challenged
generators can cause Sustained Overvoltages, as well
as ungrounded generators, and/or usual load transfer
systems.
Module Replacement & Service
The module(s) is field replaceable. Deenergize SPD, confirm with
appropriate measurement equipment and discharge internal
capacitance to ground. Mark locations and carefully disconnect
diagnostic cables, dry contact connections, phase conductors, unplug
parallel connections on TPS3 15 models, etc. Depending on model,
module may be bolted to backplane or the backplane may be part
of the module assembly. Remove module/backplane. Reinstall in
reverse order.
There are no user serviceable parts inside the module. Disassembly
is not permitted.
Modules may be returned to the factory for factory service, qualification
and return. Please contact Siemens TPS Tech Support at 888.333.3545
for assistance.
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