Accurate, economical, handheld instrument
The YSI EcoSense® instruments provide accurate data in the most affordable format. The “M” stands for memory and the instruments feature a real-time clock, larger memory and simple data transfer to a PC with a built-in USB port.
The pH100M is easy-to-use, field-worthy and provides accurate and repeatable measurements.
The pH100M measures pH, mV/ORP and temperature with the following features:
- Rugged, waterproof, field-worthy case. IP-67 rated.
- Waterproof micro-USB port for transferring data to PC; no software required.
- Holds 250 data sets; no need to write down data.
- Real-time clock for date/time stamp of saved data.
- User-selectable re-calibration prompt provides reminder to calibrate.
- Automatic buffer recognition (US or NIST buffer sets).
- Automatic or manual temperature compensation.
- 1-year instrument warranty; 6-month electrode warranty.
- 1 and 4-meter field cables available; lab pH and ORP electrodes available.
- Displays electrode efficiency.
- Autolock mode holds stable readings on display.
The pH100M is designed for quick, accurate measurements in an economical platform. Easy-to-use, waterproof and backed by a 1-year warranty, the pH100M is ideal for a wide range of applications.
| Temperature | Range | -10 to 120°C | |||||||||
| Resolution | 0.1°C | ||||||||||
| Accuracy | +0.3°C (System accuracy – instrument, sensor, cable) | ||||||||||
| pH | Range | -2 to 16 units | |||||||||
| Resolution | 0.01 unit | ||||||||||
| Accuracy | +0.01% of full scale or +0.03 pH units (System accuracy – instrument, sensor, cable: +0.2 pH units) | ||||||||||
| mV | Range | -1999 to +1999 mV | |||||||||
| Resolution | 1 mV | ||||||||||
| Accuracy | +0.1% +1 digit | ||||||||||
EcoSense pH100M Additional Specifications
| Operating range | Temperature | 0 to 50°C (32 to 122°F) |
| Relative Humidity | up to 95% | |
| Waterproof rating | IP-67 waterproof | |
| Handheld Size | 78 mm wide (widest point) x 184 mm long x 37 mm deep (3.1 in x 7.25 in x 1.45 in) | |
| Weight with battery | 280 grams (0.6 lb) | |
| ATC Probe | Thermistor, 10kΩ/25°C | |
| Battery | One 9 volt (included); 150 hour battery life; Real Time Clock (RTC) powered by non-replaceable CR2032 coin battery (3V) | |
pH Temperature Compensation Auto/Manual -10.0°C to 120.0°C (14 to 248°F)
| pH Buffer Recognition | US (4.00, 7.00 & 10.0 at 25°C or 4.00, 7.02 & 10.06 at 20°C) or NIST (4.01, 6.86, 9.18 at 25°C or 4.00, 6.87 & 9.23 at 20°C) | |
| pH Calibration Temperature | 0°C to 60 °C (32 to 140°F) | |
| pH Offset Recognition | +90 mV at pH 7.00 or 6.86 | |
| pH Slope Recognition | +30% at pH 4.00, 4.01, 9.18, or 10.01 | |
| Audio Feedback | Yes, all keys | |
| Autolock feature | Yes | |
| Auto shutoff | Automatically powers off after 30 minutes of inactivity | |
| Memory (data sets) | 250 (1 data set = pH, temperature, date/time) | |
| Re-calibration Timer | User-selectable; from 0 to 60 days | |
| Real-Time Clock (RTC) | Yes, for date/time stamp of saved data and re-calibration timer | |
| USB Port | Yes, built-in waterproof micro-USB for downloading data to a PC. No software required. |



![ACR Lithium Polymer Rechargeable Battery f/SR203 VHF Radio [1062]](https://www.ironfixaccessories.com/wp-content/uploads/2026/10/acr-lithium-polymer-rechargeable-battery-f-sr203-vhf-radio-1062.webp)


