Efficient Networks S120 manual Search for reference, travel to reference cam

Function modules 7.9 Basic positioner

	$SSURDFKGLUHFWLRQ	S
	
$		%
	5HIHUHQFHSRLQW  FRRUGLQDWH
	S
S	U	
	_Y_
		
	S
		
	S
		
5HIHUHQFHFDP	S
S
		V
5HIHUHQFH]HURPDUN
6WDUWGLUHFWLRQ		S
S		S

		S

Figure 7-18 Example: homing with reference cam

The signal on binector input p2595 (start homing) is used to trigger travel to the reference cam (p2607 = 1) if search for reference is selected at the same time (0 signal at binector input p2597 (homing type selection). The signal in binector input p2595 (start homing) must be set during the entire referencing process otherwise the process is aborted. Once started, the status signal r2684.11 (reference point set) is reset.

The software limit switch monitoring is inactive during the complete reference point approach; only the maximum traversing range is checked. The SW limit switch monitoring is, if required, re-activated after completion.

The velocity override set is only effective during the search for the reference cam (step 1). This ensures that the "cam end" and "zero mark" positions are always overrun at the same speed. If signal propagation delays arise during switching processes, this ensures that the offset caused during establishment of position is the same in each homing process.

Axes that only have one zero mark over their complete traversing or modulo range are designated with parameter p2607 = 0 (no reference cam present). After starting the homing process, synchronization to the reference zero marks is started straight away (see step 2) for these axes.

Search for reference, step 1: travel to reference cam

If there is no reference cam present (p2607 = 0), go to step 2.

When the homing process is started, the drive accelerates at maximum acceleration (p2572) to the reference cam approach velocity (p2605). The direction of the approach is determined by the signal of binector input p2604 (search for reference start direction).

When the reference cam is reached, this is communicated to the drive using the signal at binector input p2612 (reference cam); the drive then brakes down to standstill with the maximum deceleration (p2573).

If a signal at binector input p2613 (reversing cam, minus) or at binector input p2614 (reversing cam, plus) is detected during the search for reference, the search direction is

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