26
Instruction Leaflet
I. L. 29-889B
Effective June 2011
Instructions for Digitrip RMS 910 Trip Unit
eaton corporation
www.eaton.com
otee:
N
If control power is lost while you are changing the address or baud
rate, i .e .: while you are still holding-in the "TRIP RESET" push button, the
display will go blank and when the control power is restored, the Trip Unit will
still retain the previous address and baud rate values, as if you had not been
trying to change them .
NOTICE
AS SHOWN IN FIGURE 1, TO THE LEFT AND BELOW THE DISPLAY WINDOW,
IS A SPACE TO RECORD THE INCOM ADDRESS. BECAUSE TRIP UNITS
AND CIRCUIT BREAKERS OF THE SAME RATING ARE INTERCHANGEABLE,
IF MORE THAN ONE HAS BEEN WITHDRAWN FOR MAINTENANCE AT ONE
TIME, IT IS CRITICAL THAT THE EACH UNIT BE RETURNED TO ITS CORRECT
CELL LOCATION SO THAT THE CIRCUIT HAS THE CORRECT ADDRESS.
FOR EXAMPLE, IF TWO IDENTICAL BREAKERS (ONE WHOSE TRIP UNIT
ADDRESS IS "001" AND THE OTHER WHOSE TRIP UNIT ADDRESS IS
"100") WERE SWITCHED, THE INCOM
®
COMMUNICATIONS SYSTEM WILL
RESPOND PER THE INFORMATION FROM EACH TRIP UNIT'S ADDRESS
NUMBER AND NOT THE NEW CELL POSITION.
5.2 Remote Master Computer
To communicate with a remote master (IBM
®
compatible) personal
computer, install a Eaton Computer Operated Network Interface
(CONI) card or Master INCOM Network Translator (MINT) into the
computer frame (chassis) . The connections in the network are then
made by twisted pairs of wires as shown in Figure 21 .
5.3 Assemblies Electronic Monitor (AEM-II) and Breaker
Interface Monitor (BIM)
An Assemblies Electronic Monitor (AEM-ll) or a Breaker Interface
Monitor (BIM) can be applied in the same assembly with the circuit
breakers, or at a location remote from the breakers, to monitor the
information from any of the Digitrip RMS 910 Trip Units . The connec-
tions in the network are made by twisted pairs of wires as shown
in Figure 22 . The AEM-II (Style GO4 - Firmware version 7 .1 and
above) will display all Digitrip RMS 910 information except voltage
and harmonic type data . The AEM-II will pass through the voltage
and harmonic data to a network master . Digitrip RMS 910 Trip Units
should be set to communicate at 1200 Baud when applied on the
same network with Digitrip RMS 700 and 800 Trip Units (see Section
5 .1, Item 5) .
5.4 Both Remote Master Computer and AEM / BIM
When desired, Digitrip RMS 910 Trip Units can communicate with
either an Assemblies Electronic Monitor (AEM-II) or a Breaker
Interface Monitor (BIM) and a remote master computer (IBM PC
compatible with CONI or MINT card as noted in Section 5 .2) . The
connections in the network are then made by twisted pairs of wires
as shown in Figure 23 .
5.5 INCOM
®
Network Interconnections
INCOM
®
sends bursts of data on a 92 to 11 5 .2 kHz carrier at rates
up to 9600 baud, over twisted pair conductors, to interconnect the
many devices comprising the network .
Recommended cable specifications:
•
Eaton cable catalog #IMPCABLE, Style #2A95705G01;
•
Belden 9463 cable family; or
•
Identical Commscope or Quabbin cables .
These bursts of data can be captured and used in a variety of ways
depending upon the manner in which the master computer software
program is written . For example, the data for the individual phase
current values are available on the network, but the software must
select the appropriate data, decode and display it in a useful manner .
Following an over-current trip operation, the sequence of coded data
varies slightly . The cause of trip, and the value and phase (or ground)
current, responsible for the trip are available on the network . If a
TRIP were initiated due to a Short-Time Delay over-current condition,
for example, the coded message for "SDT" would be transmitted by
the Trip Unit . Once the message is received and interpreted by the
software, the value of current can be retrieved and the applicable
phase can be identified, along with the time of trip and the value of
the trip event counter . As long as control power remains available to
the Power / Relay Module, the reason for trip, and the values of cur-
rent in the other phases, including neutral and/ or ground at the time
of trip, as well as the values of each protection setting, also remain
available until the Trip Unit is reset . Effective utilization of the infor-
mation available over the INCOM
®
network requires appropriately
designed software, such as the Eaton IMPACC
®
system, or your own
custom software system .
For detailed instructions about interconnecting devices over an
INCOM
®
network, see IMPACC
®
wiring specification T .D . 17-513 .
5.6 lnformation Communicated by Digitrip RMS 910
The Digitrip RMS 910 Trip Unit utilizes the Eaton INCOM
®
serialized
protocol to send out coded messages . The coded messages can be
interpreted by system level software, such as the Eaton IMPACC
®
system, to display any of the information that is listed in Table 5 .
lnformation available for remote display includes:
•
Status of circuit breaker: "Closed", "Open", or "Tripped";
•
All Protection Settings (see Section 3);
•
All information displayed in the Trip Unit window:
•
Phase and Ground or Neutral current values,
•
Power and Energy Demand parameter values,
•
Coded Messages regarding status of the circuit .
Refer to the IMPACC
®
System Communications reference program-
ming guide (see Section 6) for more information . The information
available through INCOM
®
is actually greater than that available local-
ly through the Trip Unit display itself . For example, with INCOM
®
,
one can view the time of trip event and trip event counter remotely,
even though these values are not available for display locally in the
Trip Unit window .
5.7 Waveform Capture
The Digitrip RMS 910 can respond to a command from a remote
master to perform a waveform capture of phase currents [I
A
], [I
B
] and
[I
C
] . A total of 58 data points per phase per cycle is captured and
can be sent to a host computer . From this data, parameters such as
[THD], individual harmonics content and waveform displays can be
fabricated .
There is a timer in the Digitrip unit that will limit the acceptance of a
"waveform capture" software command to once a second . See I .L .
17-384 Appendix U . on IMPACC System Communications on wave-
form capture commands .
5.8 Remote Closing and Tripping of Circuit Breakers
The Digitrip RMS 910 Trip Unit can respond to commands from the
remote master computer to "TRIP" the circuit breaker remotely;
and furthermore, if the circuit breaker has been equipped with the
applicable optional electrical operator or spring release feature,
the Digitrip RMS 910 Trip Unit can respond to commands from the
remote master computer to "CLOSE" the circuit breaker remotely .
The CLOSE command causes the "Communications Close" contact
in the Power Relay Module to close (see wires CCI and CC2 in
Figure 2), making the circuit breaker's closing control circuit, and
releasing it to close (see the connection diagram applicable for your
circuit breaker listed in Section 6) .
When the Electrical Operator or Spring Release option is purchased
for the circuit breaker, the Communications Close contact is wired
into the close release circuit at the factory . The TRIP command
causes the Digitrip RMS 910 Trip Unit to operate the circuit breaker's
trip release (see "
T
" in Figure 2) . The trip release remains locked-
out, so that the circuit breaker cannot be reclosed, until the Trip Unit
