Low Cost, Compact Relay Ladder Logic Embedded PLCs

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I. Introduction

The H-series PLCs are a family of small, low cost, pure relay-ladder logic (i.e. No BASIC) based PLCs that are available since 1993. The family spans from the T22H with 12 inputs, 10 outputs to the T64H with 40 inputs and 24 outputs. Members of the H-series controller family differ mainly in the number of I/Os (inputs/outputs), and the type of I/Os they carry (relay or transistor outputs, PNP or NPN types, opto-isolator inputs or high voltage inputs, etc). Since each different PLC model has different wiring requirements, please refer to their respective Installation Guide on the wiring methods and installation details. The number of I/Os, timers, counters, internal relays as well as the maximum allowable program steps are also stated in the Installation Guide.

All H-series PLCs are original programmable by means of only the DOS version of TRILOGI software. However, in response to popular customers' request,  in Q4/2003 we introduced the Windows version of the TRiLOGI software - WinTRiLOGI version 3.5,  specifically for programming the H-series and E10+ PLCs.

The H-series PLCs includes the T22H-npn, T28H-Relay, T40H-Relay, T44H-pnp, T44H-npn and the T64H-Relay. The following table summarizes the number of I/Os, timers, counters and internal relays for each existing model:

Model Name	Inputs	Outputs	Internal Relays	Timers	Counters	Maximum Program Steps
T22H-npn	12	10	128	20	20	400
T28H-Relay	16	12	128	20	20	400
T40H-Relay	24	16	128	20	20	400
T44H-npn/pnp	28	16	128	20	20	400
T64H-Relay	40	24	256	40	40	800

Please note that For T22H, T28H, T40Hand T44H, an enhanced CPU option is available which provides 256 internal relays, 40 timers, 40 counters and 800 steps. These PLCs are given respective model names such as T22Hplus-npn, T28Hplus-Relay, T40Hplus-Relay, T44Hplus-pnp and T44Hplus-npn.

II. Hardware Specifications

H-series PLCs Hardware Specification Table

III. Software Features and Programming Methods

WinTRiLOGI Version 3.5
- download Help Files here

IV. Host Communications

All H-series PLC have built-in communication capability which enable a host computer to send command to read or alter any of the internal logic states of inputs, outputs, relays, timers or counters.  Click here to download the Communication Protocols.