Tempco TEC-2500, Инструкция по эксплуатации

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3–5 Heat Only Control
Heat Only ON-OFF Control: Select REVR for OUT1, set PB1 to 0, SP1 is
used to adjust set point value, O1HY is used to adjust dead band for ON-OFF
control, TIME is used to adjust the dwell timer (enabled by selecting TIMR for
A1FN or A2FN). Output 1 hysteresis (O1HY) is enabled in the case of PB1=0.
The heat only on-off control function is shown in the following diagram:
The ON-OFF control may introduce excessive process oscillation even if hysteresis is minimized to the smallest. If ON-
OFF control is set (i.e., PB1=0), TI1, TD1, CYC1, OFST, CPB and PL1 will be hidden and have no function to the
system. The manual mode, auto-tuning, self-tuning and bumpless transfer will be disabled too.
Heat only P ( or PD ) control: Select REVR for OUT1, set TI1 to 0, SP1 is
used to adjust set point value, TIME is used to adjust the dwell timer (enabled
by selecting TIMR for A1FN or A2FN). OFST been enabled in case of TI1=0
and is used to adjust the control offset (manual reset). Adjust CYC1 according
to the output 1 type (O1TY). Generally, CYC1=0.5~2 seconds for SSRD and
SSR, CYC1=10~20 seconds for relay output. CYC1 is ignored if linear output is
selected for O1TY. O1HY is hidden if PB1 is not equal to 0.
OFST Function: OFST is measured by % with range 0–100.0%. In the steady
state (i.e., process has been stabilized), if the process value is lower than the
set point a definite value, say 5°C, while 20°C is used for PB1, that is lower
than the process value by 25%, then increase OFST 25%, and vice versa. After
adjusting OFST value, the process value will be varied and eventually coincide
with set point. Using the P control (TI1 set to 0), the auto-tuning and self-tuning
are disabled. Refer to section 3-21 "manual tuning" for the adjustment of PB1
and TD1. Manual reset (adjust OFST) is not practical because the load may
change from time to time and often need to adjust OFST repeatedly. The PID
control can avoid this situation.
Heat only PID control: Selecting REVR for OUT1, SP1 is used to adjust set
point value. TIME is used to adjust the dwell timer (enabled by selecting TIMR
for A1FN or A2FN). PB1 and TI1 should not be zero. Adjust CYC1 according to
the output 1 type (O1TY). Generally, CYC1=0.5~2 seconds for SSRD and
SSR, CYC1=10~20 seconds for relay output. CYC1 is ignored if a linear output
is selected for O1TY. In most cases, self-tuning can be used to substitute for
auto-tuning. See section 3-19. If self-tuning is not used (select NONE for
SELF), then use auto-tuning for the new process, or set PB1, TI1, and TD1
with historical values. See section 3-20 for auto-tuning operation. If the control
result is still unsatisfactory, then use manual tuning to improve control. See
section 3-21 for manual tuning. The TEC-2500 contains a very clever PID and
Fuzzy algorithm to achieve a very small overshoot and very quick response to
the process if it is properly tuned.
Setup ON-OFF:
OUT1=
PB1=0
Adjust:SP1, O1HY, TIME(if enabled)
SP1+O1HY/2
SP1 O1HY/2
SP1
ON
OFF
OUT1 Action
PV
Dead band = O1HY
Time
Time
Figure 3.2 Heat Only
ON-OFF Control
Setup P:
OUT1=
TI1=0
CYC1 (if RELAY, SSRD or SSR is
selected for O1TY)
Adjust:
SP1, OFST, TIME (if enabled),
PB1(
≠
0), TD1
Setup PID:
OUT1=
O1TY
CYC1 if RELAY, SSRD or SSR is
selected for O1TY)
SELF=NONE or YES
Adjust:
SP1, TIME (if enabled), PB1(
≠
0),
TI1(
≠
0), Td1
Auto-tuning:
Used for new process during initial
tuning
Self-tuning:
Used for a process any time.
Manual Tuning:
May be used if self-tuning and auto-
tuning are inadequate.