Siemens LME7 Series Basic Documentation

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Building Technologies Division Basic Documentation LME7... CC1P7105en
Infrastructure & Cities Sector 27 PWM settings 29.11.2011
permissible ignition speed close to the overvoltage limit. If this is not observed, there
is a risk of loss of safety functions.
27.4.2 Reading the value of parameter 920 in the prepurge
phase (P30) and ignition load phase (P38, P40 and P44)
Procedure
 Set the ignition load speed (P0) for the burner to the maximum permissible value,
and the prepurge speed (503.01) to the minimum value
 Let the AZL2... display service mode. Press
/
reset
for >3 seconds. The display first
shows InFo, then SEr
 Release
/
reset
so that parameter number 701.00 starts blinking
 Press
or to select parameter 920 (blinking)
 Start the burner
 Read the value of parameter 920 in the prepurge phase (P30) and ignition phase
(P38, 40 and 44). Write down the values. They will be required as a basis for
setting safety parameter 675.00
 By pressing
ESC
(press and simultaneously) you leave the parameter
setting level and return to the initial mode

Note:
If the onboard operating panel of the LME7... basic unit changes from phase display
(e.g. P30) to SEC at 1-second intervals, or if the LME7... goes to lockout (Loc: 225),
the difference between the actually required PWM value (parameter 936) and safety
parameter 675.00 or 675.01 is too small. Decrease value 675.00 (parameter 920 -
1%) or increase value 675.01 (parameter 920 +1%). Reduce the value until SEC
disappears from the display.

Siemens LME7 Series Specifications

General

Brand	Siemens
Model	LME7 Series
Category	Controller
Language	English