HED251-T

**HED251 | HED261 Electronic Switch Closure Totalizer** 

The HED 251-T/261-T are miniature electronic counters (24mm x 48mm) designed for either direct PCB mounting or panel mounting and is ideally suited to battery powered applications. With 4 digit (HED 251) and 8 digit with upto 10kHz high speed input (HED 261) options, these totalizers feature the latest CMOS circuitry to achieve very low quiescent current consumption and are backlit for visibility. The HED counters are ideal for contact closure and reed switch signal inputs and are suitable for a range of OEM applications. 

## **Key Features** 

- Uses the latest CMOS circuitry to achieve very low quiescent current consumption 

- 10mm/8mm black character high contrast LCD display 

- Integral backlight 

- Counts pulses up to 18Hz frequency (HED251) or 20Hz/10kHz (HE261) 

- External reset input 

- CE and RoHS compliant 

## **Specifications** 

## **HED 251** 

4 digit, black LCD, 10mm characters Leading zeros blanking 

## **Display** 

**Count Range** 0-9999 

**Count Input** Contact closure open collector input. 18Hz max, negative edge triggered, 0.7V threshold 1.8V max, 25mS min pulse width 

## **HED 261** 

8 digit, black LCD, 8mm characters Leading zeros blanking 

0-99999999 

- High speed input (pin3) 10kHz max negative edge triggered, 0.7V threshold 18V max, 50uS min pulse width 

- Contact closure open collector input (pin2). 20Hz max, negative edge triggered, 0.7V threshold 18V max, 15mS min pulse width 

**Supply voltage** 3.0 VDC **Count Speed** Up to 18 Hz **Current consumption** Counter - <10μA, typically 5μA, backlight -  40mA max **Operating Temperature** -10°C to +50°C **Storage Temperature** -20°C to +70°C **Certifications** CE, RoHS **Reset Option** Non-Reset 

2.7 – 3.3V DC 

Up to 20Hz and 10kHz 

## **Dimensions** 

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## **Part Numbers** 

**HED251-T** 4 Digit Panel Mount Counter **HED261-T** 8 Digit Panel Mount Counter 

**Trumeter (Europe) Trumeter (The Americas)** Pilot Mill 6601 Lyons Rd, Suite H-7, Alfred Street Coconut Creek, Florida Bury, FL 33073, BL9 9EF USA Tel: +44 161 674 0960 Tel: +1 954 725 6699 Email: sales.uk@trumeter.com Email: sales.usa@trumeter.com 

**Innovative Design Technologies Sdn. Bhd** Lot 5881, Lorong Iks Bukit Minyak 1 Taman Perindustrian Iks, 14000 Bukit Tengah Penang, Malaysia Web: www.idtworld.com Tel: + 604 5015700 Email: sales.my@idtworld.com 

**www.trumeter.com** 

HED251-261-DS-v.1.0             01/2021