General Information

Inverters (Variable Frequency Drives or VFD’s) provide an economical means of regulating the speed and performance of motors. Inverters have gained a prominent place in today’s industrial and commercial arena. But as dependable as modern inverters are, they still malfunction and cease operation, generally at the worst possible moment. For this reason, several methods of isolating the inverter have been developed. Until now these methods involved expensive and unreliable contactors, relays, and timers. Advance Controls' Patented IBYSS ® (Inverter Bypass Safety Switch) eliminates all of these unreliable methods of removing the power from the inverter drive.

The IBYSS ® is a manually operated "Positive Break" switch. It does not rely on relays, contactors, or timers; all of which can burn out and stop the application from running. The "Positive Break" feature mechanically ramps the contacts open. The IBYSS ® does not use springs (as used in contactors and relays) to open the contacts.

Should the inverter malfunction, the IBYSS ® is manually switched from the “DRIVE” to the “LINE” position. This redirects power around the inverter straight to the motor and completely removes all power from the inverter. This provides total isolation of the inverter from both the incoming power line and the outgoing line to the motor. Since the power to the inverter is completely cut off, the inverter can be serviced or even removed, while the application is operating at full
speed / full power. The IBYSS ® is the answer for a low cost, direct acting, straight forward and reliable means of providing an inverter bypass and total isolation of the inverter during a malfunction while still providing full power directly to the application.

The IBYSS ® is also furnished with a "TEST" position. This "TEST" position allows power into the inverter for setup and diagnostics, but does not allow power to the application. The "TEST" position simplifies the installation and maintenance of the inverter.

All IBYSS ® can be customized for specific applications. Enclosures, switching patterns, connections, etc. can be customized to meet unique needs.

Operation

“Drive” (Normal) Position
Incoming Power is routed through the Inverter Bypass Safety Switch to the inverter drive, from the inverter drive back through the switch and then to the application.

“Off” Position
Incoming Power is stopped at the Inverter Bypass Safety Switch.
No power is routed to either the inverter drive or to the application.

“Line” (Bypass) Position
Incoming Power is routed through the Inverter Bypass Safety Switch directly to the application (motor). In the "bypass" position, no power is routed to the inverter drive from either the incoming power line to the switch or from the outgoing power line to the application. In the "bypass" position, power is completely removed from the inverter drive. The application continues receiving full - direct power.

“Test” Position
Incoming Power is routed through the Inverter Bypass Safety Switch to the Inverter Drive. No power is allowed from the switch to the application. The "TEST" position allows calibration, adjustments and diagnostics to be performed on the inverter drive without allowing the power to flow on to the application. This position allows easy setup for the inverter drive.

Features

• "OFF" position functions as a UL508 Motor Disconnect
• Manual operation with positive break contacts for reliable circuit transfer
• No contactors, relays, solenoids or coils to consume power, stick or burn out
• Complete isolation of the Inverter from both the incoming and outgoing power
• Full voltage across the line motor starting up to 50 HP
• Full voltage Contactor / Starter starting up to 400 HP
• Gold Flash auxiliary contacts for reliable control signals to PLC's and other logic level devices
. . . Furnished with either 1 or 2 auxiliary contacts
. . . With 1 auxiliary the contact closes in the "LINE" position
. . . With 2 auxiliaries, one contact closes in the "LINE position and one contact closes
. . . in the "DRIVE" position
• "TEST" position - Standard - allows power into the inverter without allowing power
• to flow to the application
• Switches can be door mounted or sub panel mounted
• 3 styles of Handle Assemblies are available:
. . . Selector style - non-lockable
. . . Lockout style - meets OSHA 1910 requirements
. . . Panel mount disconnect style - meets OSHA 1910 requirements and
. . . locks enclosure door closed
• Basic open switch for inclusion in customer's panel
• Factory assembled in an enclosure with easy to wire Terminal Strip for simple field installation
• UL cUL Listed through 125 amps and 125 HP
• UR and cUR recognized through 400 Amps and 400 HP
• U.S. Patent #5,721,449