The Diamondback switch is a solid dielectric, threephase load break switch for overhead applications. The Diamondback switch combines the time-proven reliability of vacuum bottles with the maintenance-free benefits of a solid dielectric insulated device. Diamondback is designed for three phase automatic or manual switching operations providing circuit isolation for systems rated up to 25.8 kV, 630 A continuous current. The compact, light-weight design provides ease of installation. Diamondback has been designed and tested to comply with the IEC 62271-103 standard (formerly IEC 60265-1:1998).
SOLID DIELECTRIC MODULES
The solid dielectric modules utilize a time-proven solid dielectric epoxy insulation to fully encapsulate each of the three vacuum interrupters. The operating temperature range of the switch is -30ºC to +50ºC (-22ºF to +122ºF). A 1000:1 ratio current transformer with +/-1% accuracy is encapsulated into each solid dielectric module. There are six (6) internal voltage sensors that allow for voltage measurement on both the source and load side of the device. These voltage sensors are encapsulated inside the solid dielectric modules and have an accuracy of +/-3%.
FEATURES AND BENEFITS
| FEATURES |
BENEFITS |
| Solid dielectric Insulation, uses no oil, SF6 or greenhouse gases |
No maintenance or monitoring system necessary, common with oil of SF6 insulation. Solid dielectric provides lowest total lifecycle cost. |
| Solid dielectric material is inert, environmentally friendly |
| Easy to automate with the control and FTU-P200 |
Smart Grid Ready |
| Integrated six voltage sensors |
Less equipment & weight on pole reduces future maintenance. Less congestion on pole improves reliability. Enables full line metering capability for Smart Grid applications. |
| Compact size and lightweight construction |
Allows for installation in tight areas and eases handling during installation |
| Reversible alley arm frame |
Frame is reversible and provides installation flexibility in switch orientation. |
ELECTRICAL RATINGS
| Maximum Voltage |
25.8kV |
| Continuous Current |
630A |
| Frequency |
50Hz/60Hz |
| Short Circuit Current, 1 second rms |
12.5kA |
| Making Current Peak |
32.5kA / 5 times |
Current Switching Capacity
Tested per IEC 62271-103 |
Load Current |
630A / 200 times (100%) |
| 31.5A / 20 times (5%) |
| Loop Current |
630A / 20 times |
| Cable charging Current |
25A / 10 times (100%) |
| 7.5A / 10 times (30%) |
| Line charging Current |
1.5A / 10 times |
| Exiting Current |
22A / 10 times |
| No voltage |
5000 times |
| Control input voltage |
1 Ø 220VAC / 120VAC |
| Control voltage |
24VDC |
| Power Frequency Withstand Voltage |
Dry |
60kV / 1min |
| Wet |
50kV / 10sec |
| Surge Withstand Voltage |
150kV (1.2 times / 50 microseconds) |
APPLICATIONS
Switches play a fundamental role in improving distribution reliability. By applying Diamondback switches in strategic locations on the distribution system, faults can be isolated to minimize the outage area, loads can be distributed according to system conditions, critical loads can be kept on-line, individual protective devices or sections off-line can be bypassed during routine maintenance, and loads can be dropped to prevent overloading the source. In short, switches are typically used to reconfigure a distribution system to minimize outages and increase system reliability.
MANUAL SWITCHING
By installing manually operated switches, a user can economically redistribute power during times of planned outages for routine line maintenance, equipment replacement, or even seasonal load adjustments. Manual switches can also be used to isolate faults in areas where immediate power restoration is not necessary, or to perform an emergency sectionalizing function to quickly restore power to the customers affected by a power outage. The Diamondback switch does not require deenergizing the system prior to switching so customer service is not disrupted.
AUTOMATED SWITCHING
By adding a controller to the Diamondback switch, the user can perform all of the functions of a manually operated switch without having to dispatch a crew to the switch site. Additionally, current and voltage can be monitored via SCADA.
FAULT ISOLATION
When combined with a control, the Diamondback switch can be used as an automatic sectionalizing device for automatic fault isolation. Six voltage sensors and three current transformers are provided as a standard feature on the Diamondback switch. Most logic schemes require a fault interrupting device to be upstream from the sectionalizing switches. The protective device must be either locked out or programmed for a specific reclose interval plus a time safety factor to allow
Application Example: Diamondback paired with a Cobra Recloser
- A fault occurs between Diamondback sectionalizer and Load 2
- The Cobra recloser starts reclosing sequence: trips open, closes, trips open
- The Diamondback sectionalizer opens after 2nd overcurrent trip
- The Cobra Recloser closes and restores power on the line between the Cobra Recloser and Diamondback Sectionalizer
TIE SWITCHES
For tie applications, the Diamondback switch control senses a voltage loss on either the source or the load side to determine whether or not to close in from a normally open condition between two different sources. Once the voltage on one source has been lost for a pre-programmed period of time, the tie switch will close in restoring power to the de-energized line. Current transformers "tell" the controller that a fault exists when the main contacts are closed. For a normally open tie, the tie may close into a fault upon loss of voltage on one feeder. The control “knows” of the faulted condition and would not open unless it detects a loss of voltage on the faulted feeder side, signifying the upstream protective device has operated. On a normally closed tie, the switch control would use similar logic, but no fault closing would be necessary prior to isolating the fault. Tie switches can also be applied to automatically bypass a feeder which has been locked out due to a failure, planned outage or a faulted line. If the switch closes into a fault, the tie switch would open once the upstream protective device has opened, de-energizing the line.
LOOP SCHEMES
Loop schemes generally consist of two or more sources tied into a distribution system to ensure backup power is available when the primary feeder is lost. The scheme utilizes sectionalizing and tie switches to automatically isolate the fault and restore power to all areas unaffected by the fault quickly and reliably using the same principles and methods described previously.
AUTOMATIC TRANSFER
For critical load applications such as hospitals, processing plants, military bases, etc., automatic transfer schemes are common. For overhead systems, this scheme requires two switches, voltage sensors and current transformers and a voltage-time controller. A loss of voltage on the primary source is sensed and initiates the controller to open the primary and close the alternate source switch to automatically restore power.
SCADA / DISTRIBUTION AUTOMATION
Switches can perform the above functions either autonomously or through a SCADA system where the switch controls incorporate FTUs for interfacing with a master station. A variety of SCADA applications are available which employ either a master-slave or peer-to-peer communications architecture.
LAZER AUTOMATION
The distribution automation expertise and products of G&W and the high end software knowledge of Survalent Technology, our software company, have been combined to provide a state of the art solution – Lazer Automation. Three levels of Lazer solutions are available; Lazer I for peer-to-peer product applications, Lazer II for stand-alone controller based systems, and Lazer III for total system wide management and control.
DATASHEET
