Broyce Control Ltd., Pool Street, Wolverhampton, West Midlands WV2 4HN. England
Tel: +44 (0) 1902 773746 Fax: +44 (0) 1902 420639 Email: [email protected] Web: www.broycecontrol.com
The information provided in this literature is believed to be accurate (subject to change without prior notice); however, use of such information shall be entirely at the user’s own risk
.
P9620-2-A
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1
1
1
XXXXXX
P
Type: P962
Type: P962
Type: P962
Type: P9620
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0
0
Definite Time (DT)
Definite Time (DT)
Definite Time (DT)
Definite Time (DT) Earth Fault Relay
Earth Fault Relay
Earth Fault Relay
Earth Fault Relay
True R.M.S. measurements
Adjustable Low-set tripping threshold
Adjustable High-set tripping threshold with option to disable
Adjustable Definite Time setting (applicable to Low-set triggering only)
Instantaneous tripping on High-set triggering
Test and Reset button for simulating and clearing of fault condition
Red LED indication of Low-set or High-set triggering and tripping
Green LED indication for Auxiliary power supply presence
Microprocessor based (self checking) with non-volatile memory
Terminals suitable for 2 x 2.5mm
2
wires (complete with protective cover)
•
GENERAL OVERVIEW
The P9620 (from the P9600 series family of IDMT/DT relays) is a microprocessor based relay
designed to monitor and detect Earth faults in 3-phase applications. Typically the P9620 is
wired in conjunction with external current transformers of the feeder to be protected.
The adjustments and indicators are laid out such to help the user during set-up and fault
finding. The adjustment for the Low
Low
Low
Low----set
set
set
set for example has its corresponding red LED positioned
above it so it is clear to which function this LED relates to. The same also applies to the High
High
High
High----
set
set
set
set adjustment and LED. Adjustment and LED operation is explained further on the next page.
The adjustable time delay Delay
Delay
Delay
Delay is assigned to the Low
Low
Low
Low----set
set
set
set triggering only. The High
High
High
High----set
set
set
set does
not have any adjustable delay and hence will trip instantaneously if triggered. If required, the
High
High
High
High----set
set
set
set can be set to disabled.
A Test mode is provided (also accessible with the tamperproof transparent cover closed) to
confirm the correct operation of the internal relay. The relay will energise when the “TEST”
“TEST”
“TEST”
“TEST”
button is pressed and de-energise when the “RESET”
“RESET”
“RESET”
“RESET” button is pressed.
•
OPERATION
Example 1.
When an Earth fault occurs and the level of current exceeds the
“Low
“Low
“Low
“Low----set Io>”
set Io>”
set Io>”
set Io>” trip threshold, the corresponding red LED above the
adjustment illuminates. If the current remains for greater than the time
delay set by the adjustment marked “Delay”
“Delay”
“Delay”
“Delay”, the relay will then
energise. The red LED will then flash indicating a tripped condition.
If the fault current has been removed, pressing the “RESET”
“RESET”
“RESET”
“RESET” button
will return the relay back to normal operation. The red LED will then
extinguish.
Example 2.
If a fault current occurs such that it exceeds the “High
“High
“High
“High----set Io>>”
set Io>>”
set Io>>”
set Io>>” trip
threshold (and before the “Delay”
“Delay”
“Delay”
“Delay” has had time to elapse), the relay
will de-energise with no delay. The red LED above the “High
“High
“High
“High----set
set
set
set
Io>>”
Io>>”
Io>>”
Io>>” adjustment will flash.
In the event of an Earth fault condition, the basic sequence of
events is shown below.
Assuming High-set trip is enabled.
•
PRESENTATION
1.
“Delay”
adjustment* 5.
“Low-set triggered”
red LED indication
2.
“Low-set Io>”
trip adjustment* 6.
“High-set triggered”
red LED indication
3.
“High-set Io>>”
trip adjustment* 7.
“TEST”
button
4.
“Power supply”
green LED indication 8.
“RESET”
button
* accessible only when the front cover is open
START
EARTH FAULT
occurs
Low-set I
o
>
triggered
Run delay
t>
High-set
I
o
>>
triggered?
N
Y
TRIP!
Delay
t>
complete?
N
Y
Dims:
W x H. 96 x 96mm (front)
W x H. 89.5 x 89.5mm (main body)
L. 107mm