Annunciator Purge Setup

From EMIT Controls

There are two features related to unit purge:

  1. Low Purge Alarm
  2. Automated purge sequence

Note that either auto-crank or an ECU is needed for these features

Low Purge Alarm

Purge-limit.png

The purge alarm is used to specify a minimum suction level to allow the engine to start. In the above screenshot, this is 10 psi. If the suction is below 10 psi, starting the engine will always go directly to FAULTED. If unused, this can be set to 0.

The sensor used for suction does not have to be specified- the system will find the analog input with the name "Suction", "Suction Stg 1", etc.

Purge Sequence Setup

The purge sequence can be used to automatically purge the engine on startup. It requires the presence of a system-controlled suction, bypass, and blowdown valve. The suction valve can be set up as a suction block valve or a proportional suction PID loop. The setup is found at “Settings” -> “Brain” -> “Outputs Setup” -> “Purge Sequence Setup”. The general sequence is:

  1. Blowdown, bypass, and suction are closed
  2. Blowdown opened; suction opened (slowly if possible)
  3. Bypass opened
  4. Blowdown and suction closed

There are a variety of detailed settings in the sequence, see the setup page for more information.

The purge sequence will not actually be entered unless the “Low Purge Alarm” mentioned above is set to something other than zero. If the suction is below the setting at startup, the purge sequence will run before pre lube.