ABB DPU 1500R Instruction Book page 178

ABB Distribution Protection Unit 1500R/2000R
ZSC in the DPU-2000R
You can activate the ZSC feature by running the DPU1500R/2000R Operations software "WinECP." Select Settings
from the Main Menu and then select Programmable Inputs. Get the data from the DPU1500R/2000R and assign
ZSC to one of the programmable inputs. Now you can remotely enable or disable the ZSC function via its programmed
input terminals. With the relay's rated voltage applied to the ZSC terminals, the function is enabled. Conversely,
without rated voltage applied to the ZSC terminals, the function is disabled. The status of the ZSC input terminals
can be viewed by selecting Test in the main menu and then selecting Contact Inputs. The contact input status can
be viewed with WinECP and the man-machine interface LCD display. All Zone Sequence Coordination steps are
stored in the Operations Record logs.
To ensure correct Zone Sequence Coordination operation, the protection engineer must adhere to the following
criteria when setting the relays. Assume the backup DPU1500R/2000R is RELAY #1 and the down-line DPU1500R/
2000R is RELAY #2.
1. RELAY #1 must be set for a longer instantaneous time than RELAY #2. The recommended minimum
coordination margin is .1 seconds.
2. RELAY #1 time overcurrent settings must be programmed for a longer delay than those of RELAY #2.
3. The 79 reset time of RELAY #1 must be programmed greater than the largest open interval time of RELAY
#2.
Breaker
Position
Open
Down-line
DPU1500R/2000R
Closed
Enabled Element
Open
Backup
DPU1500R/2000R
Closed
Enabled Element
Figure 13-22. Down-line and Backup Recloser Operations with ZSC
13-16
79-1 79-2
Delay
Delay
(50) (50)
(51)
ZSC ZSC ZSC
Step
Step Step
(50) (50)
(51)
website:www.abb.com/papd
79-3
Delay
(51)
(51)
L
O
C
K
O
79-4
U
Delay
T
(50 or 51)
ZSC
Step
(50 or 51)
Time
Applications Notes
9/99