Electromechanical Bypass (EMB2) Operation
5.1.2 EMB2 Auto Bypass
General Information
Auto bypass allows a fault condition in the drive to activate running the motor in bypass without operator intervention. Activation of the function is through setting DIP switches (S100) located on the EMB2 bypass control card (see Figure 5.1). A fault condition enables a delay timer prior to tripping the drive into bypass. The fault trip and running in bypass are reported as output from the bypass control card. The auto bypass function is built in.
Prior to Enabling Auto Bypass
•Complete the
WARNING
HAZARDOUS VOLTAGE!
Remove power to the bypass panel before setting auto bypass dip switch settings. Bypass can contain high voltage. Failure to remove power to bypass panel before setting dip switches could result in death or serious injury.
Operation
•With the bypass selector switch in drive and auto bypass enabled, a fault signal from the drive will activate the auto bypass timer.
•If the fault clears before the time delay is complete, the motor remains operating in drive mode. This allows temporary faults, such as a momentary under or over voltage, to clear without transferring the system to bypass.
•If the timer completes its cycle before the fault clears, the panel trips into bypass mode and the motor runs at constant full speed from line input voltage.
•In bypass, the motor will stop if safety or motor overload conditions are exceeded.
•Once auto bypass is activated, the only way to reset the unit back to drive is by operator intervention. Ensure that the fault has been cleared, then rotate the bypass switch to the OFF position momentarily before setting it back to the drive position. This resets the drive and fault timer.
Auto Bypass Function Setup
Enable auto bypass by closing one or more DIP switches on switch S100 located on the bypass control card. (Times are approximate.)
•All OFF = no auto bypass operation
•Switch 1 only ON = 30 sec. delay
•Switch 2 only ON = 60 sec. delay
•Switch 3 only ON = 300 sec. delay (maximum)
•Switch 4 = Always OFF
5.1.3 EMB2 Common Run/Stop
General Information
The common run/stop function provides remote run and stop control of the motor in bypass. Without common run/ stop, the motor would automatically run at full speed whenever the bypass is activated. The remote signal provides drive control as well as bypass control, making this one input common to both. Common run/stop is enabled by factory default. When used with the run permissive function, common run/stop permits run request operation in bypass.
Prior to Enabling Common Run/Stop
•Complete the
Operation
•A user supplied remote start command wired to connector X55, terminals 3 and 4 initiates remote bypass operation. With common run/ stop, bypass mode cannot be activated by hand on the drive keypad or by serial communication.
Common Run/Stop Setup
•Wire input terminals 3 and 4 on connector X55 per the system application.
To Disable Common Run/Stop
•Common run/stop is enabled by factory default when ordered.
•To disable the feature, turn switch four on dip switch S105. This allows the bypass to start when the bypass switch is placed in the bypass position.
•Remove wire from terminal 18 of the drive control terminal and insulate the end of the wire to prevent shorting. This is required or the drive will always have a run command.
•If applicable, connect remote run/stop input to terminals 12 and 18 on the drive control card.