Ropex RESISTRON RES-440, Руководство по эксплуатации

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Startup and operation
Version 1 RES-440 Page 31
perature diagnosis function can thus be explicitly deactivated, e.g. if the temperature drops temporarily owing to
the closure of the sealing jaws.
9.3.11 Heatup timeout (as of software revision 100)
The heatup timeout can be parameterized with step 219 in the Configuration menu ("0" = OFF).
This timeout starts when the START signal is activated. The RES-440 then monitors the time required for the
ACTUAL temperature to reach 95% of the SET temperature. If this time is longer than the parameterized time, the
corresponding error code (304) is indicated and the fault relay is switched (
 section 10.26 "Fault areas and
causes" on page 81).
9.3.12 Configuration of the alarm relay
The alarm relay is set with step 215 [31] in the Configuration menu.
There are two possible settings:
1.
"Normal" (Factory setting)
Alarm relay contact closed by a fault
2. "Inverse"
Alarm relay contact opened by a fault
9.4 Heatsealing band
9.4.1 General
The heatsealing band is a key component in the control loop, since it is both a heating element and a sensor. The
geometry of the heatsealing band is too complex to be discussed at length here. We shall therefore only refer to
a few of the most important physical and electrical properties:
The measuring principle applied for this system necessitates a heatsealing band alloy with a suitable temperature
coefficient TCR, i.e. one whose resistance increases as the temperature rises.
Too low a TCR leads to oscillation or uncontrolled heating.
When heatsealing bands with a higher TCR are used, the controller must be calibrated for this.
The first time the heatsealing band is heated to approximately 200…250°C, the standard alloy undergoes a once-
only resistance change (burn-in effect). The cold resistance of the heatsealing band is reduced by approximately
2…3%. However, this at first glance slight resistance change results in a zero point error of 20…30°C. The zero
point must therefore be corrected after a few heating cycles (
 chap. 9.4.2 „Burning in the heatsealing band“,
page 32).
Set
95% of Set
Actual value
Time
Heatup time Error code
304
Timeout