Model YBO-R/SCI(RED) is a Loop Isolator, which is fully compatible with  Hochiki’s ESP analogue addressable protocol. The YBO-R/SCI(RED) Base has  been designed to be used with the CHQ-WS2 Wall Sounder. 
 
The Base incorporates an amber LED to show when it is isolating a section of the loop. The YBO-R/SCI(RED) does not use an address, and has the same wiring configuration as the standard YBN-R/3 Sensor Base making it very simple to install.