DT3000
Instruction Leaflet
I.B. 17555D
Effective: Date 07/02
Page 17
For more information visit:
www.cutler-hammer.eaton.com
Supersedes I.B. 17555C dated November 1999
•
Switch S8 is used to enable/disable the ability to
download Set Points from the communication interface
(host computer).
•
Switch S9 is used to select whether the relay should
be self-reset or manually reset (lock out function). For
additional information please refer to the “Manual
Reset”
and “Auto Reset’ sections.
In the manual reset mode the Trip Instantaneous
contact (TB2 12 and 13), Trip Overcurrent contact
(TB2 14 and 15) and the Trip Alarm contact (TB2 6, 7
and 8) change state after a protection trip operation.
The contacts stay in that state until the “Reset”
Pushbutton is pressed. In addition, the front panel will
hold the cause of trip in the “Trip Cause” window and
the fault current magnitude in the “RMS Ampere”
window. A RESET COMMAND can be sent to the
Digitrip 3000 by a master computer to remotely reset
the Digitrip 3000.
In the auto reset mode the Trip Instantaneous
contacts (TB2 12 and 13), or Trip Overcurrent
contacts (TB2 14 and 15) are momentarily closed after
a protection trip operation. The contacts will remain
closed until the current drops below 0.5 A. The Trip
Alarm Relay, however, remains energized until the
“Reset” Pushbutton is depressed or a RESET
COMMAND is received from a communication system
master. In this mode after a trip is initiated and the
current is removed, the display will BLINK the cause of
the trip in the “Trip Cause” window and the “RMS
Ampere” window will show the fault current magnitude.
Both displays clear when current is reapplied.
•
Switch S10 is reserved.
Inverse Time Overcurrent Reset
: The inverse-time
overcurrent function in the DT3000 requires the measured
current to be below pickup for 4 cycles before the trip
accumulator is reset. The multi-cycle reset counter
eliminates concern that the integration will reset during an
arcing fault and slow down tripping.
Communicating LED
: A red LED just above terminal
block (TB2) is used when the relay is communicating. If the
relay is the type designed to accept field installation of a
communication module at a later date, this LED is not
functional at any time.
Terminal Block One (TB1)
: TB1 is located on the left side
of the rear panel, and is numbered 1 through 15, with 1, 2,
3, 7 and 8 not used. Terminals 5 and 6 are provided for
the AC or DC input control power connections. Terminal 4
is the connection for equipment ground. Terminal 9 and
10 provide for connection to a required dry 52b contact and
to a 52 TOC contact from the circuit breaker.
When the
relay has input control power, Terminals 9 and 10 will
have this potential on them.
Terminals 11 and 12 are used for ground zone
interlocking, inverse time overcurrent protection and short
delay protection. The zone interlocking function is a low
level dc signal used to coordinate with “downstream” and
“upstream” breakers that see or do not see the fault. If the
function is not used but an inverse time overcurrent or
short delay time is desired, the two terminals should stay
jumpered as they were when shipped from the factory.
Terminals 13 and 14 are used for phase zone interlocking,
inverse time overcurrent protection and short delay
protection.
Terminal 15 is the zone signal common.
Zone common
should never be connected to earth ground.
Refer to
Figure 4-1 for a typical phase zone interlocking / wiring
scheme.
NOTE: DIGITRIP 3000 PROTECTIVE RELAYS ARE
SHIPPED WITH A PHASE ZONE INTERLOCKING
JUMPER (ACROSS TERMINALS TB 1-13 AND 14) AND
A GROUND ZONE INTERLOCKING JUMPER (ACROSS
TERMINALS TB 1-11 AND 12). FOR PHASE OR
GROUND ZONE CAPABILITY, THE RESPECTIVE
JUMPERS MUST BE REMOVED.
Terminal Block Two (TB2):
TB2 is located on the right
side of the rear panel and is numbered 1 through 15.
Terminals 1 and 2 are used for the internal INCOM
communications interface.
Terminal 3 is used to reference the INCOM cable shield. It
is capacitively tied to ground for high frequency noise
immunity purposes.
Terminals 4 and 5 are a N.O. contact from the
Communications Close output relay that can be configured
two different ways:
1. When Dip Switch S5 is in the “On” position, this output
relay is programmed to close when the High Load
timer times out.
2. When Dip Switch S5 is in the “Off” position the
Communications Close Relay can be energized via a
specific communications message sent over the
INCOM port.
Terminals 6, 7 and 8 are Form “C” contacts on the trip
alarm relay and change state whenever any protective trip
is initiated by the relay. They do not change state when the
master computer initiates an opening of the circuit breaker
via the communication interface. After a protective trip, the
contacts remain in the changed state until the “Reset”
Pushbutton is pressed, whether the relay is in Manual
Reset Mode or Auto Reset Mode.
Terminals 9,10 and 11 are Form “C” contacts on the
protection off alarm relay. The contacts change state when
nominal control power is applied to the relay and no
internal errors are detected.
