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Start-up ramps:
On start-up, the zones in automatic mode are heated gradually until they reach their operating setpoint.
There are four possible types of start-up ramps:
Duration ramp
The system heats at the maximum gradient of A,
then maintains the temperature at B for a period
of C minutes.
During cooling, gradient E will be applied
down to temperature I, considered cold.
Gradient ramp
The system heats at the maximum gradient of A.
During cooling, gradient E will be applied
down to temperature I, considered cold.
Synchronized ramp
y
The system automatically selects the zones which
are working properly (no failed thermocouples or
heating elements), and then starts heating these
zones. An algorithm allows the fastest zones to
follow the temperature evolution of the slowest
zones, within the maximum gradient A.
During cooling, slope E will be
applied down to temperature I, considered cold,
and the fastest zones will follow the slowest zones.
Staggered ramp
gg
This ramp uses the grouping of zones in
manifold or nozzle groups (§3.1.2.4). Initially all
the zones in "manifold" type groups are heated
in a synchronized ramp, while the zones in
"nozzle" type groups are kept at temperature B
for a period of time C. When all the zones in the
"manifold" groups have reached their particular
setpoints, the system stabilizes their heating by
means of a waiting time D, and then executes
a synchronized ramp on the zones in the
"nozzle" groups. The staggered ramp is terminated
when all zones have reached their operating
setpoints.
During cooling, the nozzles will be
fi
rst cooled and then stabilized at temperature
F for a period of time G, then the blocks will be
cooled at the same temperature, then stabilized
for a period H. Finally, all zones will be cooled
down synchronously to temperature I, considered
cold.
