Efficient Networks S120 manual Bypass with synchronization with overlap p1260 =

Vector control 4.20 Bypass

●Synchronizing the motor to the line supply. For all bypass versions, the following applies:

●The bypass is always switched-out when one of the control word signals "OFF2" or "OFF3" is withdrawn.

●Exception:

When required, the bypass switch can be interlocked by a higher-level control so that the drive converter can be completely powered-down (i.e. including the control electronics) while the motor is operated from the line supply. The contactor interlocking should be implemented on the plant/system side.

●When the drive converter restarts after POWER OFF, the state of the bypass contactors is evaluated. After powering up, the converter can thereby change straight into "Ready to start and bypass" status. This is only possible if the bypass is activated via a control signal, the control signal (p1266) is still present once the system has been ramped up, and the automatic restart function (p1200 = 4) is active.

●Changing the converter into "Ready to start and bypass" status after powering up, is of a higher priority than switching back on automatically.

●Monitoring of the motor temperatures using temperature sensors is active while the converter is in one of two statuses "Ready to start and bypass" or "Ready to operate and bypass".

●The two motor contactors must be designed for switching under load.

Note

The examples contained in the following descriptions are only basic circuits designed to explain the basic function. The dimensions of specific circuit configurations (contactors, protective equipment) must be calculated for specific systems.

Prerequisite

The bypass function is only possible for sensorless closed-loop speed control (p1300 = 20) or V/f control (p1300 = 0...19) and when an induction motor is used.

Commissioning the bypass function

The bypass function is part of the function module "technology controller" that can be activated when using the commissioning Wizard. Parameter r0108.16 indicates whether it has been activated.

4.20.1Bypass with synchronization with overlap (p1260 = 1)

Description

When "bypass with synchronization with overlap (p1260 = 1)" is activated, then motor is transferred, synchronized to the line supply and is also retrieved again. During the changeover, the two contactors K1 and K2 are simultaneously closed for a time (phase lock synchronization).

160	Drive Functions
	Function Manual, (FH1), 07/2007 Edition, 6SL3097-2AB00-0BP4