West Control Solutions Pro-8 - Manual (Page 56)

8 Special functions
8.1 Start-up circuit
The start-up circuit is a special function for temperature control, e.g. hot runner
control. High-performance heating cartridges with magnesium oxyde insulation
material must be heated slowly to remove moisture and prevent destruction.
Operating principle:
1 After switching on the supply voltage, line-out to the start-up set-point SP.St
is using a maximum start-up correcting value of Y.St.
2 The start-up holding time t.St is started one K below the start-up set-point
( SP.St-1K).
3 Subsequenlyt, the process is lined out to set-point W.
4 If the process value drops by more than 40 K below the start-up set-point
( SP.St-40K) due to a disturbance, the start-up procedure is re-started ( 5, 6, 7 ).
g
With W < SP.St, W is used as set-point. The start-up holding time t.St is omitted.
g
If the gradient function ( PArA/ SEtP/ r.SP ¹ OFF) was selected, start-up value
SP.St is reached with the adjusted gradient r.SP.
g
With the boost function (see chapter 8.2) selected, W is increased by SP.bo
during time
t.bo .
The following settings can be selected:
SP.Fn = 10 set-point + start-up circuit
The start-up circuit is effective only with the internal set-point.
SP.Fn = 11set-point, SP.E /SP.2 + start-up circuit
The start-up circuit is effective also with the external set-point SP.E and the 2nd
set-point SP.2.
Special functions
Start-up circuit 56
Pro-8
W
Set-point Process
value
Power on Disturbance
t
SP.St
t r t.St t r t.St
SP.St-1K
SP.St-40K
1 2
3 4 5 6 7