Nederman L-PAK Series, Manual

L-PAK 150/250 Standard

7

EN

4.2 

Unit operation modes

L-PAK 150/250 Advanced has the following four operation modes:

1. 

Off mode

2. 

Standby mode

3. 

Running mode

4. 

Idling mode

See Section 

5.1. Status messages

 for more information about each mode. How the unit 

moves from one operation mode to another is explained below. See also Figure 1 for a flow 

chart showing how the unit goes through its four different operation modes.
When the unit is in Off mode, the unit can be put into Standby mode (the unit is ready) 

with its motor off and the Filter Cleaning Valve (FCV) closed by pressing the Standby/

Running button. While the unit is in Standby mode, the unit can be put back into Off mode 

again by pressing the Standby/Running button.
The unit goes from Standby mode into Running mode when it receives a pilot signal by a 

valve being opened at one or more work stations (in other words, someone starts to work). 

The unit’s motor is now on and the FCV is closed. The DIR_Time and SSR_Time timers are 

not started, see Sections 

6.2.4. DIR_Time

 and 

6.2.3. SSR_Time

.

The unit stays in Running mode as long as there is an active pilot signal. However, the unit 

can still be put into Off mode by pressing the Standby/ Running button.
Note that if only one workstation is connected to the unit, or if only one work station is 

in use and work stops at that one station, the pilot signal stops. If there is more than one 

work station connected to the unit, and more than one work station is in use, the pilot 

signal only stops if work stops at all workstations (in other words, all valves close).
When the pilot signal stops, the DIR and SSR timers start. If work resumes at one or more 

work stations within 10 seconds, the unit stays in Running mode. The DIR and SSR timers 

are reset back to zero and are stopped.
If DIR_Time is set for 10 seconds (default), and the pause in work is longer than 10 seconds, 

DIR_Time elapses. The unit then goes into Idling mode with its motor on and the FCV open.
If a new pilot signal is sent within 12 minutes, the unit goes back into Running mode. The 

DIR and SSR timers are again reset to zero and are stopped. However, if SSR_Time is set for 

12 minutes, which is the default setting, and there is no new pilot signal within 12 minutes, 

SSR_Time also elapses.
The unit then goes into Standby mode until it either receives a new pilot signal that puts 

the unit back into Running mode, or the unit is turned off (in other words, put into Off 

mode) by pressing the Standby/Running button.

5 

PLC messages

The following sections show the different status, warning and alarm messages that can be 

seen in the PLC display.

5.1 

Status messages

The following status messages give information about what mode the unit is in or what 

routine service is being performed.