Super Systems AC20 User Manual

Page 52

BURN OFF PROCEDURE

(Available only if “O2” is not selected as primary control
variable)

The Burn off function allows to remove the carbon or soot
deposit inside the probe. It is carried out by putting air into the
probe; the oxygen present in the air will burn the carbon deposit.
The Purge function is used to evacuate the not combusted air
present in the probe after the Burn off (for details see the probe
instruction manual).
The Burn off procedure may be carried out:
- manually (by pressing TST + MAN keys), or
- by external contact (Dig.3), or
- by serial link, or
- automatically, after a period (set by the "bF.tr" [R.H03]

parameter) started from the end of the previous Burn off
procedure.

The Burn off procedure cannot be carried out if:
1) The first part of the SMART algorithm (TUNE) is in progress.
2) Five minutes are not elapsed from instrument power on or from

the end of another procedure (Burn off or Probe test).

3) The probe temperature is less than 1000 °F (538 °C) or in

error condition.
Note

Note

Note: the temperature value will not be taken into account if
mV is the selected controlled variable and "t.t.Ac" parameter
[C.I07] is equal to "nO".

NOTES:

NOTES:
a) If one or more conditions previously described still exist the

automatic Burn off will be frozen, the state of these conditions
are checked by the instrument every minute.
During this time, the instrument operates as previously set
before the Burn off request.
When the checking will be successful, these conditions no
longer exist and the automatic Burn off will be immediately
performed.
The timer programmed to perform the next Burn off will start
only at the end of the previous Burn off.

b) If the procedure is requested by keys and it cannot be started,

the following information is displayed for 2 seconds:
Upper display: burn
Middle display:inh
Lower display: Number of the first not complied condition (1, 2
or 3 previously described).
Once these conditions no longer exist, repeat manually the
Burn off starting command.

During the Burn off procedure, the upper display shows "burn" or
"PurG", while the middle display shows the remaining time to end
the related procedure.
The lower display shows the probe value in mV, the information
shown on this display may be changed as described in the
"Display function"paragraph (see pag. 43).