gefran 1000 Manuel D'utilisation page 16

• SOFTWARE ON/OFF FUNCTION
Turning off: you can deactivate the instrument by simultaneously pressing the F and
Lower keys for 5 seconds. The instrument goes into "OFF" status, similar to shutdown
status except that power is not turned off. During this "OFF" status, the display is off,
with the decimal point flashing on the second digit of the lower display to indicate the
presence of line voltage; all outputs (control and alarms) are in OFF status (logic level,
0, relays de-energized), and all instrument functions are inhibited except for the "Turn-
on" function.
Turning on: press the "F" key for 5 seconds to switch the instrument from "OFF" to
"ON" status. The instrument will run a setup cycle identical to a power-on, with flashing
of all display segments for about 5 seconds, followed by normal functioning according
to the HW and SW configuration. If the instrument is configured with self-tuning or soft
start enabled, the appropriate procedure will be run as if following a power-on. If line
voltage is cut during "OFF" status, at the next power-on the instrument will go to the
same "OFF" status ("ON/OFF" status is saved). The function is normally enabled. The
function is disabled by setting parameter Pro = Pro + 8 in phase CFG2.
• ALARM FUNCTIONS
Alarms can be absolute or deviation, direct or reverse, symmetrical deviation.
Absolute alarm: limit set with an absolute value compared to 0 (Ex. for 1000: setpoint =
400, AL1 = 450, AL2 = 350, AL3 = 500).
Deviation alarm: limit set with an offset compared to setpoint (Ex. for 1000: setpoint =
400, AL1 = +50, AL2 = -50, AL3 = +100).
Direct alarm: corresponding relay energized with controlled variable over set limit, in
both absolute and deviation mode (maximum alarm).
For HB alarm, relay energized if current is below set value.
Reverse alarm: corresponding relay energized with controlled variable under set limit,
in both absolute and deviation mode (maximum alarm).
For HB alarm, relay energized if current is above set value.
With symmetrical deviation alarm, the offset relative to the setpoint is both added and
subtracted, defining an intervention window.
With absolute alarms, the limits take on at maximum the limits set in phase CFG2 (Lo.S
and Hi.S).
With deviation alarms, the limits have values in range -199/+999 and the set value is
added algebraically to the setpoint (the deviation alarm limit may extend below the
lower limit or above the upper limit of the set scale).
• CT (current transformer) INPUT
This input signals changes in load input, indicating the current value at the ammeter
input in the set scale range.
The CT card (signaled by the brd code) lets you read the current in the CT secondary
(5Aa.c) on the auxiliary analog input (terminals 6 and 7; see connection diagram). You
can define the full scale current value directly referred to the load circuit with the Hb.S
parameter in CFG.1 phase (example: for a CT 75/5A, set Hb.S = 75.0); by default,
scale start is considered 0. Current reading is available in phase 5 in work mode (the
lower display shows the whole value of current followed by letter "A;" example: 45.A), or
in the setting phase for the HB alarm limit on the upper display with resolution of a tenth
of an Ampere (ex. 45.8).
Notes:
- The CT card lets you access the ammeter input calibration procedure (Hb.C).
- The CT input function can be used independently of the HB alarm to simply display
11 • SELF-TUNING / AUTO-TUNING / SOFT-START / AUTO-MAN
TURNING ON SELF-TUNING
If enabled, this function starts when the instrument is turned on or by simultaneously
pressing the F and Raise keys for 3 seconds. The controlled variable flashes on the
display.
Self-tuning can be used only for heating systems. For very fast systems (100°C/min)
limit PtU self-tuning power.
The function starts by supplying power (PtU). When temperature is reached (Setpoint-
room temperature)/2, it turns power off and begins a wait phase to identify parameters.
The procedure ends with resumption of control, which uses the calculated parameters.
When the self-tuning phase ends (i.e., when peak is reached), the calculated parame-
ters are saved and any preset parameters are lost.
To interrupt self-tuning when in progress, simultaneously press the F and Raise keys
for 3 seconds (press F first). The upper display stops flashing and the self-tuning func-
tion is deactivated and disabled (code S.tu in Phase 0 is automatically changed).
Repeat this procedure to activate the self-tuning function (if enabled).
With self-tuning enabled, the term "SOF" in CFG1 is replaced by PtU power value sup-
plied in self-tuning phase in range 0...100%.
By setting Pt U = 0 Pt.U = 100% by default.
TURNING ON AUTO-TUNING
If enabled, this function starts when the setpoint is reached for the first time (± 4 scale
points).
The corrective action is on the value of the proportional band.
Auto-tuning is suspended each time the setpoint is changed, and the control parame-
ters are returned to their starting values.
Action resumes when the new setpoint is reached. The proportional band cannot be
changed during auto-tuning: you have to disable auto-tuning to do this.
TURNING ON THE SOFT-START FUNCTION
If enabled, this function partializes power as a percentage of the time elapsed since
instrument turn-on compared to the time set (0...99.9 min) ("SOF" parameter, phase
CFG1).
Soft-start is an alternative to self-tuning, and is activated after each instrument turn-on.
10 • FUNCTIONAL NOTES
the current at the ammeter input.
HB ALARM (Heater Break Alarm)
This type of alarm is conditioned on use of the current transformer (CT) input with set-
ting of the brd code in phase CFG.2. The HB alarm function is independent of alarms
AL1, AL2, AL3.
Enable by setting the Out code in phase CFG.2 to an odd value (bit1 = 1).
Enabling allows setting of the limit in work mode phase 4, with display of the ammeter
input on the upper display and the limit with letter A flashing on the lower display (ex.
25.A).
Press the Raise and Lower keys instead of letter A to show the decimal figure of the
limit, which remains during the change.
When the keys are released, "A" reappears after one second.
With code A.r.F in phase CFG.2, you can assign the HB alarm to each of the alarm out-
puts installed (AL1, AL2, AL3). If it is not assigned to an output, the alarm state is still
available in read via serial line (if enabled) at address 10H (see Memory Map section).
The HB alarm function is selectable from 4 different modes by means of code Hb.F in
phase CFG.2:
0 - alarm trips when load current drops below limit set for ON time of main output (eval-
uation time: 30 sec. including ON); turns off as soon as limit is exceeded.
1 - alarm trips when ammeter full scale (Hb.S) in OFF time is exceeded by 12%; turns
off as soon as value drops below 12% limit.
2 - alarm trips if one of functions 0 and 1 (described above) is active (OR logic between
functions 0 and 1)
3 - HB alarm for continuous output (PWM control, setting Ct = -1 or -2); with fixed duty
cycle of 100msec.; does not take account of ON/OFF times and presupposes a special
ammeter card with HW integration of load current.
The alarm trips if current drops below the set limit for 15 sec.
Functions only with power in output greater than 10% (2% for version 12); otherwise
the alarm is deactivated. The alarm resets automatically if its cause is eliminated.
Deactivate the HB alarm by setting the limit to 0.
Note:
- ON/OFF times refer to the set cycle time (see CT parameter in Programming phase 0).
LBA ALARM (Loop Break Alarm):
This alarm identifies interruption of the control loop due to a possible probe in short cir-
cuit, reversed probe, or load break.
If enabled (Lb.t <>0), it causes an alarm in case the variable value doesn't increase in
heating (or doesn't decrease in cooling) under conditions of maximum power supplied
for a set time (Lb.t) in range 0...240 min.
If the value of the variable is beyond the proportional band, power is limited to the set
value (Lb.P) in range 0-100%.
The active alarm condition is signaled by flashing of the displays. By means of code
A.r.F (in phase CFG.2) the LBA alarm can be assigned to each of the alarm outputs
installed (AL1, AL2, AL3).
If it is not assigned to an output, the alarm state is still available in read via serial line (if
enabled). The alarm condition resets if the temperature increases in heating (decreases
in cooling), or by means of the panel keys by simultaneously pressing the F and Raise
keys for 3 seconds (press F first).
The LBA function is disabled by setting parameter Lb.t to 0.
AUTO/MAN FUNCTION, MANUAL CONTROL OF OUTPUT WITH BUMPLESS AT
SWITCH TO AUTOMATIC
In normal operation, press the F key. After a scan of the alarm limits (and load cur-
rent if applicable), the lower display shows the percentage of power supplied in out-
put in the range 0...99% followed by letter P, while the upper display shows the
process variable (PV).
99% is considered maximum power. This data remains on the display until the F key is
pressed again, which returns the display to normal condition (PV/SP).
In MAN mode, you can set the control (power) output from the panel keys in the range
0.0...99.9%.
MAN mode is activated by simultaneously pressing the Raise and Lower keys in output
display phase (indicated by letter P on the lower display).
You can set power in the above-mentioned range by means of the Raise and Lower
keys.
In change phase, letter P is replaced by the decimal figure of the power level, which
resumes flashing when the key is released.
99% is considered maximum power.
When switching to manual, the instrument delivers either the last manual power level
saved or the automatic power at the time of switching, depending on the mode selected
(Ctr code) configuration phase CFG.2. Press the F key to return to Automatic.
Switching from Manual to Automatic takes place in "BUMPLESS" mode if the process
variable is within the proportional band.
The manual power value is saved. If the instrument is configured as ON-OFF controller:
In Automatic:
Main output = ON, corresponds to displayed power = 99;
Main output = OFF, corresponds to displayed power = 0;
In Manual:
Set power <= 49.9 corresponds to main output = OFF;
Set power >= 50.0 corresponds to main output = ON;
You can disable the MAN/AUTO function by setting the software protection to "Pro" =
"Pro" + 16.
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