Pixsys STR551 Process Indicator 48×96 mm, OLED, RS485

STR551 is a 48 x 96 mm panel indicator from Pixsys for temperature and process signals. A 2.42 inch monochrome OLED graphic display shows the process value, trend and bar graph, a universal analogue input accepts thermocouples, RTDs, mA, volts, mV and potentiometers, and two 2 A relays, two analogue outputs, two digital inputs and RS485 are included. It is sold as STR551-12ABC-T128R.

An indicator that logs, totalizes and retransmits

Compared with a basic panel meter the STR551 adds functions normally found in a data logger. The manual describes peak values (maximum, minimum and peak-to-peak), a totalizer that integrates a flow signal on a per-hour or similar time base, a sum function that adds the process value on command for weighing applications, and a customizable linear input with up to 16 steps for non-linear transmitters.

The data logger can store process values at a sampling time of 1 to 3600 seconds in the controller memory; the manual says they can be read over Modbus from address 5001 or wirelessly from the RFID memory. The text menus come in English, Italian, German, French and Spanish, and the unit can be set up by NFC from a smartphone, through the memory card or by micro USB with MyPixsysLab.

From the datasheet

• Universal 16-bit input: thermocouples K, S, R, J, T, E, N, B; PT100, PT500, PT1000, Ni100, Ni120, PTC 1K, NTC 10K, NTC 2252; 0-1/5/10 V, 0/4-20 mA, 0-60 mV; potentiometer 1 to 150 kΩ.
• Customizable linearization, totalizer and sum, trend visualization from 0.1 s to 3600 s.
• Analogue retransmission: 0-10 V and 0/4-20 mA outputs for the input value.
• Alarm modes absolute and band, instantaneous, delayed or retentive, sensor failure and activation by serial line.
• Programmable by NFC/RFID through the MyPixsys app; RS485 Modbus RTU.

Technical specification

STR551 data

STR family and ordering

The same 48 x 96 mm platform carries four models in the datasheet: STR551 (process, temperature, mA and V indicator), STR561 (strain-gauge indicator for load cells and melt-pressure sensors), STR571 (Modbus RTU remote display, master and slave) and STR581 (frequency counter and tachometer). STR551-12ABC-T128R is the code to quote when the signal is a thermocouple, RTD, 4-20 mA or voltage signal.

Digital inputs can be programmed for run, hold, tare zero, alarm reset, totalizer reset, peak reset, sum and configuration lock. When the datasheet and the manual differ on operating temperature (0 to 45 versus 0 to 40 °C) apply the lower value in panel design.

Setup notes from the manual

At first start the display asks for the language, then shows process pages, a trend graph and a bar graph; the keys are multifunction with their meaning printed next to each key. The latch-on function lets you teach the scale limits from a transmitter or potentiometer by placing the sensor at minimum and maximum and storing both values, with an optional virtual zero.

The totalizer example in the manual uses a 4-20 mA sensor with 9000 m3/h full scale: set the totalizer to hour and the unit integrates 2.5 m3 every second at full flow. Values must be stored to EEPROM through the store parameter. For supply wiring the manual asks for cables of at least 18 AWG rated above 70 °C and an external switch or breaker near the equipment.

Applications

Typical roles are pressure, level, flow and temperature readouts on pump skids, boiler houses and water treatment panels, where a 4-20 mA signal feeds a local display, high and low alarm relays and a 0-10 V retransmission to a PLC. The data logger helps where a supervisory system is not yet installed.

Selection and installation notes

A temperature controller or process indicator is selected from the input sensor, the range, the outputs it must drive and the panel space. Match the sensor type and range, choose the output to suit the load (relay, SSR drive or analog), run the auto-tuning with the process at normal load, set the alarm limits and keep a record of the final parameters. Use a separate protection device where overheating would be dangerous.

Information needed for a quotation

Send the full model code, the quantity, the delivery location in Oman or the GCC, the intended use and any accessories needed, so that the complete package can be quoted together.

Documents and supply information

The manufacturer data sheet is attached to this page and should be read together with the project specification and the site risk assessment before a purchase is confirmed. Ratings, standards and dimensions are quoted as printed on that sheet. Lead time, stock position and certificates available with the shipment are confirmed in the quotation, and we supply to Oman and the wider GCC region for industrial, utility and building services projects.

Related items

USB memory card (code 2100.30.013) and the MyPixsysLab software. For load-cell weighing choose STR561; for a Modbus remote display STR571.

Frequently asked questions

Which display does STR551 use?

A 2.42 inch yellow monochrome OLED graphic display with 128 x 64 pixels.

What outputs are fitted?

Two 2 A relays, a 0-10 V output and a 0/4-20 mA output, plus RS485.

Can it totalize a flow signal?

Yes. The totalizer integrates the process value over a selected time base, and a sum function adds values on command.

How is it configured?

By keys, NFC with the MyPixsys app, memory card or micro USB with MyPixsysLab.

Is Seven Star LLC a Pixsys distributor?

No. Seven Star LLC is not a Pixsys distributor; it is an independent Muscat-based supplier that quotes Pixsys products on request.

Documents and quotation

This page carries the official Pixsys datasheet and manual for STR551. Seven Star LLC is an independent supplier in Muscat and sources Pixsys products on request; tell us the quantity and delivery point to receive a quotation. Always confirm the order code and technical values in the documents first. See more in the product category.