The VTSC100 Logic Controller Board is at the heart of every Vigilant Automatic Transfer Switch. It is designed to provide all basic transfer switch control functions with simplicity, flexibility, and durability. It allows for the automatic transfer of an electrical load to a stand-by power source in the event of an over/under voltage or frequency condition on any or all phases of the normal power supply.
Features include:
• Powered from genset battery for isolation against line transients
• Integrated voltage and frequency sensing
• Adjustable transfer delays using on-board potentiometers
• Fused remote start contact relays
• Adjustable drop-out & pick-up values for voltage and frequency
• Internal test switch included
• Easy-to-use, 7-day exerciser clock gives you full control over day and time
In the event of an over/under voltage or frequency condition of utility power, the onboard VTSC100 sensing circuitry will begin the initiation of the transfer process. Upon initial sensing of a loss of utility power the Vigilant series transfer switch is specifically designed to allow an engine start time delay period (TDES) to expire before starting the generator. This engine start time delay is user adjustable from the VTSC100 preventing unnecessary engine starts from a temporary loss of utility. In the event the utility source is not restored after the engine start time delay has expired the remote contacts will close sending a signal to the generator’s automatic start controller.
When the VTSC100 senses that the generator has started, and is within acceptable limits, the transfer switch will wait until the normal to emergency time delay (TDNE) has expired before switching to the neutral position. While in the neutral position the transfer switch will transfer back to normal supply if the utility is restored. With no utility source the transfer switch will stay in the neutral position until the delay on neutral time has expired allowing the transfer switch to temporarily stop at the neutral position during either the normal to emergency or emergency to normal transfers. The temporary stop allows controlled isolation between both normal and emergency sources. After the neutral delay has expired the transfer switch will complete the transfer to the destination source. All connected loads will be transferred to the emergency power source.
While the transfer switch is in the emergency position, the VTSC100 will constantly monitor the utility source voltage and frequency status. Once the utility source is restored the transfer switch will wait until the emergency to normal time delay (TDEN) has expired before switching to the neutral position. The TDEN delay is user adjustable from the VTSC100 to prevent unnecessary transfers caused by momentary utility restoration conditions. If the utility source remains stable after the emergency to normal time delay expires the transfer switch will transfer to the neutral position. The transfer switch will stay in the neutral position until the delay on neutral time has expired. If the utility source fails during this delay period, there will be a transfer back to the emergency position. When the delay on neutral time expires the transfer switch will transfer to the normal position. All connected loads are transferred to the normal power source.
When connected loads are transferred back to the normal power source an engine cooldown period (TDEC) will be initiated allowing the generator to run in a no load condition. This engine cooldown time delay is user adjustable from the VTSC100 allowing the generator to continue running for an adjustable period after the normal utility is restored.