Yaskawa E7B Drive Bypass - Manual (Page 28)

Physical Installation 1 - 16
Switch Selectable Functions:
The slide switches used to select these functions are located on the relay controller Printed Circuit Board (PCB) A2
(See Figure 1.9). The factory default is for these functions to be de-selected.
Smoke Purge: When enabled (switch S105) this function allows a contact closure, between terminals 17 and 18 of
TB1, to transfer motor operation to bypass for a maximum capacity smoke control function. When in smoke purge
mode, during emergency fire/smoke situations, the motor overloads and safety interlock circuit are overridden to shift
the priority to protecting people rather than equipment.
Auto Transfer to Bypass: If enabled (switch S103), the E7 Bypass unit will automatically transfer the motor operation
from Drive to Bypass in the event of a Drive fault. When the Drive fault condition has cleared, this function is reset
by moving the circuit breaker to the OFF position, waiting for the keypad to go blank, then switching back to the
DRIVE position.
Remote Transfer to Bypass: When selected (switch S104) this function allows a contact closure from a BAS, between
terminals 25 and 26 of TB1, to transfer motor operation from Drive mode to Bypass mode. This remote tranfer to
Bypass function overrides the DRIVE/BYPASS manual switch.
Fig 1.9 Printed Circuit Board A2
IMPORTANT
Before selecting this function in fan applications, care must be taken to ensure that the duct-work is
designed to handle the pressure resulting from full speed operation with the VAV terminal unit dampers at
minimum position or closed.
Slide Switches
PCB Jumpers