# RB420 LCD Paperless Recorder

> Machine-readable summary of https://www.rbflowmeter.com/products/rb420-paperless-recorder — generated from the same product record the HTML page renders.
> R&B Instrument Inc..

## Facts

- **Model:** RB420
- **Category:** Process Instruments & Sensors
- **Canonical page:** https://www.rbflowmeter.com/products/rb420-paperless-recorder
- **Language:** en
- **Last updated:** 2026-10-18
- **Brand:** R&B Instrument Inc.

## Overview

Low-cost LCD paperless recorder with 1–4 universal input channels for logging industrial temperature, flow, pressure and other field signals.

## Description

### Product Overview

The RB420 is a low-cost paperless recorder that accepts universal mA/V/mV, thermocouple and RTD inputs on 1–4 fully isolated channels, logging temperature, flow, pressure and other field signals in the standard 160×80 mm panel cut-out.

Internal storage holds 180 days of data at 1-minute intervals with 10-year retention, and USB 2.0 or RS485 Modbus RTU export feeds plant historians and reporting software directly.

## Specifications

| Parameter | Value |
| --- | --- |
| Channels | 1–4 universal inputs, fully isolated (400 V p-p) |
| Accuracy | Basic error ±0.5% ±1 LSB; signal input ±0.2% F.S. |
| Input signals | Universal mA/V/mV/TC/RTD; frequency 2–10 kHz; pulse 0–5 kHz |
| Output | 2× current output (4–20 mA / 0–10 mA); relay alarms; 1× 24 VDC supply |
| Storage | 180 days at 1-min interval; data retained 10 years |
| Communication | USB 2.0, RS232/RS485 Modbus RTU |
| Power supply | 220 VAC ±10%, 50 Hz ±2 Hz |

## Key specifications

- Accuracy: ±0.2% F.S. (signal input)
- Pipe size: —
- Output signal: 2× 4-20mA/0-10mA output, relay alarm, RS232/RS485 Modbus RTU, USB

## Features

- Monochrome 320×200 LCD in the standard 160×80 mm panel.
- Stores 180 days at 1-minute interval; data retained for 10 years.
- USB 2.0 data export; RS232/RS485 with standard Modbus RTU.
- Supports channel accumulation and shift/daily/monthly/annual reports.
- Configuration file backup and export.
- Digital, bar-graph and curve display modes.

## Contact

For pricing, lead time and customization, contact R&B Instrument Inc. via the product page above.