Zenith ZBTS-D Bypass Isolation Delayed Transition Series ATS
The ZBTS-D Series incorporates the features of the ZBTS Bypass-Isolation Switch with those of the ZTSD unit for transfer of large motor loads, transformers, uninterruptible power supplies (UPS) systems, or load shedding to a neutral “off” position.
In critical systems such as those of hospitals and airports, power cannot be interrupted for maintenance and testing of automatic transfer switches (ATSs).
In such circumstances, a bypass-isolation switch is essential and often required by code. The GE Zenith Controls ZBTSD Series Delayed Transition Transfer/Bypass-Isolation Switch meets requirements for inspection and/or maintenance of the delayed transition transfer switch without power interruption.
The ZBTS-D Series incorporates the rugged construction of all our ZTS Series switches with a quick-make/quick-break manual load transfer handle and our control/interlock system, consisting of both mechanical and electrical interlocks.
The bypass uses normal failure sensing and a time delay to start the engine automatically if a failure occurs when the ATS has been removed for service.
Features and Benefits
- Load is not interrupted during bypass operation
- High close-in and withstand capability
- Temperature rise test per UL 1008 conducted after overload and endurance tests in unventilated enclosure – exceeds UL requirements
- Available in ZBTS (utility-generator), ZBTSU (utility-utility), ZBTSG(generator-generator) and ZBTSM (manual) configurations; models include standard, delayed, and closed transition
- Transfer switch is located on a draw-out mechanism to facilitate maintenance
- Emergency power systems can be electrically tested without disturbing the load
- Power cables do not have to be disconnected to remove transfer switch
- Bypass to any available source with transfer switch removed
- Engine start circuit maintained during bypass operation; normal power failure causes engine start contact closure even with the ATS removed
- Diagnostic lights and detailed instructions for simple step-by-step operation
- Mechanical and electrical interlocks ensure proper sequence of operation
- Bypass switch contacts are closed only during the bypass-isolation operation
- Silver-plated copper bus interconnection of the transfer and bypass switches on all sizes
- Ratings 100 to 4000 amperes
- 2, 3 or 4 poles
- Open type, NEMA 1, 3R, 4, 4X and 12
- Available with ZTS, ZTSD and ZTSCT Series Transfer Switch
- Bypass and transfer switch have identical ratings
- Suitable for emergency and standby applications on all classes of load, 100% tungsten rated through 400 amps
- UL 1008 listed at 480 VAC
- CSA C22.2 No. 178 certified at 600 VAC
- IEC 947-6-1 listed at 480 VAC
Product Specifications: Brochure for ZBTS Series (pdf)