PLCs, DCSs & Controllers


Mini programmable controllers

March 2001 PLCs, DCSs & Controllers

T1s are the micro programmable controllers in Toshiba's popular T-series family. Being members of the T-series family means that all programs written for a T1 will run on other T-series controllers. The T1s are palm-sized controllers with CPU, I/O and power supply all in one small block.

The HP911A handheld programmer and the T-PDS programming software program the entire family of T-series programmable logic controllers, from the micro T1-16 I/O to the T2N-2048 I/O. Sub-routines, interrupt functions, indirect addressing, For/Next loops, Increment/Decrement, Pre-derivative real PID are standard programming functions on the T1. These functions and the ability to process data at high-speed allow the T1 to meet the high-speed data manipulation required by sophisticated machine control applications.

The T1's RS232-C programmer port can be connected directly to computers, operator interface units, etc and accept read/write commands. An RS485 multidrop network of up to 32 T1s can be established over up to 1 km and remote programming/monitoring via modem (radio or telephone) is possible.

The T1 has two high-speed counter inputs. These 5 kHz counters can be used independently for discrete parts count in applications requiring high-speed compare, reset and strobe. The counters can also be used together as a quadrature pulse encoder counter. The two transistor outputs (DC models only) can generate a variable frequency output (5 kHz max) and can be used to drive a stepper motor. Each T1 has two adjustable pots that vary the value in two separate registers. These registers can be used as presets for timers and counters, maximum, minimum or equal values for comparisons, add or subtract adjustments, etc.

The T1Super has 8K step of program memory and 4K words of data memory. Several programs and recipes can be easily loaded into a T1S. In the 4K memory mode, it is possible to make program changes and write to the built-in EEPROM online. This feature is very important in process control applications where it is not always possible to stop the process just to add an additional interlock or permissive.

The T1S has a realtime clock/calendar for the year, month, week, day, hours, minutes and seconds. It can be used for performing scheduled operations (ie each Monday at 6 pm), time and date stamping event occurrences, etc. The realtime clock/calendar is backed up by built-in capacitor. The back-up period is more than seven days (25°C).

The device also has a built-in RS485 multipurpose communication port which can operate in one of three different modes:

Computer link mode

The T-series computer link protocol can be used in this mode. A maximum of 32 T1Ss can be connected to a master computer, operator interface station, or other higher-level controller. In this mode, the computer can read and write to all the registers in the T1S. The T-series PLC programming software (T-PDS) can also be used in this configuration to program each of the T1Ss.

Free ASCII mode

In this mode, user defined ASCII messages can be transmitted and received. A terminal, printer, bar-code reader, or other serial ASCII device can be directly connected to the T1S. This mode allows the T1S to communicate with other PLCs (T1, T2E, T2N, etc), inverters, motor protection relays and other devices with a simple ASCII read/write protocol.

Data link mode

In this mode, two PLCs (any combination of T1S, T2E or T2N) can be directly linked together. This direct link is inexpensive, easily configured and requires no special programming.

TM Automation

(011) 867 2737

[email protected]





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