Tempco TEC-2500, Инструкция по эксплуатации

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1
Unique
** High accuracy 18-bit input A–D
** High accuracy 15-bit output D–A
** Fast input sample rate (5 times/second)
** Two function complexity levels
** User menu configurable
** Pump control
Chapter 1 Overview
1–1 Features
* Fuzzy plus PID microprocessor-based control
* Automatic programming
* Differential control
* Auto-tune function
* Self-tune function
* Sleep mode function
* "Soft-start" ramp and dwell timer
* Programmable inputs(thermocouple, RTD, mA, VDC)
* Analog input for remote set point and CT
* Event input for changing function and set point
* Programmable digital filter
* Hardware lockout and remote lockout protection
* Loop break alarm
* Heater break alarm
* Sensor break alarm and bumpless transfer
* RS-485, RS-232 communication
* Analog retransmission
* Signal conditioner DC power supply
* A wide variety of output modules available
* Safety UL/CSA/IEC1010–1
* EMC/CE EN61326
* Front panel sealed to NEMA 4X and IP65
T EC-2500 Fuzzy Logic plus PID microprocessor-based controller
incorporates a bright, easy to read, 4-digit LED display which
indicates the process value. Fuzzy Logic technology enables a
process to reach a predetermined set point in the shortest time,
with the minimum of overshoot during power-up or external load
disturbance. The units are housed in a 1/32 DIN case, measuring
24mm x 48mm with 98mm behind-panel depth. The units feature
three touch keys to select the various control and input
parameters. Using a unique function, you can put up to five
parameters at the front of the user menu by using SEL1 to SEL5
found in the setup menu. This is particularly useful to OEM's as it
is easy to configure the menu to suit the specific application.
TEC-2500 is powered by 11–26 or 90–264VDC/AC supply,
incorporating a 2 amp control relay output, 5V logic alarm output
and a 2 amp alarm relay output as standard with a second alarm
that can be configured in the second output for cooling purposes
or as a dwell timer. Alternative output options include SSR drive,
triac, 4–20mA and 0–10 volts. TEC-2500 is fully programmable
for PT100, thermocouple types J, K, T, E, B, R, S, N, L, 0–20mA,
4–20mA, and voltage signal input, with no need to modify the
unit. The input signals are digitized by using an 18-bit A to D
converter. Its fast sampling rate allows the TEC-2500 to control
fast processes such as pressure and flow. Self-tuning is
incorporated. Self-tuning can be used to optimize the control
parameters as soon as undesired control results are observed.
Unlike auto-tuning, self-tuning will produce less disturbance to
the process during tuning, and can be used at any time.
Digital communications formats RS-485, RS-232 or 4–20mA
retransmission are available as an additional option. These options
allow the TEC-2500 to be integrated with supervisory control
systems and software, or alternatively to drive remote displays,
chart recorders, or data loggers.
Two different methods can be used to program the TEC-2500.
1. Use the keys on the front panel to program the unit manually or
2. use a PC with setup software to program the unit via the RS-
485 or RS-232 COMM port.
For nearly a hundred years, PID control has been used and has
proven to be an efficient controlling method by many industries,
yet PID has difficulty dealing with some sophisticated systems
such as second and higher order systems, long time-lag systems,
during set point changes and/or load disturbances, etc. The PID
principle is based on a mathematical model which is obtained by
tuning the process. Unfortunately, many systems are too complex
to describe precisely in numerical terms. In addition, these
systems may vary from time to time. In order to overcome the
imperfections of PID control, Fuzzy Logic was introduced.
What is Fuzzy Control? It works like a good driver. Under
different speeds and circumstances, he can control a car well
based on previous experience, and does not require knowledge of
the kinetic theory of motion. Fuzzy Logic is a linguistic control
which is different from numerical PID control. It controls the
system by experience and does not need to simulate the system
precisely as a PID controller would.