
Y S I Environmental
EcoSense®
pH100 pH or mV/Temp Instrument
Accurate, economical handheld measurement 
YSI’s new line of compact, handheld instruments provides the most 
accurate data in the most affordable format. e instruments feature 
an easy-to-use interface, one-hand operation, water resistant case, 
and low cost of ownership over the life of the product. e pH100    
measures pH or mV and temperature with the following features: 
• Watertight housing
• Internal buffer recognition
• Auto/Manual temperature compensation
• Sensors are available as single parameter or combinations   
 for pH or mV and temperature
The pH100 with one of the 
possible configurations using 
a combination 2-in-1 pH 
sensor and temperature sensor. Another option allows 
for a mV or pH sensor with a 
separate temperature sensor 
or flat tipped and piercing 
tipped probes. 
Pure
Data
for a
Healthy
Planet.
®
• Low battery indicator
• Electrode offset recognition
• Autolock mode holds stable readings on display
• Displays electrode efficiency
e pH100 is designed for quick, accurate results in an economi 
cal platform. e ability to measure pH, mV, and temperature in a 
simple, compact instrument allows the instrument to be used in mul 
tiple applications. With a one-year instrument warranty, six-month 
electrode warranty, calibration backup, and a variety of cable/elec 
trode options, the pH100 will fit your needs. 
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-
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Compact design and 
affordable price
www.YSIEcoSense.com

Y S I Environmental
To order, or for more 
information, contact        
YSI Environmental.
+1 937 767 7241 
800 897 4151 (US)
www.ysiecosense.com
YSI Environmental 
+1 937 767 7241 
Fax +1 937 767 9353 
environmental@ysi.com
Endeco/YSI 
+1 508 748 0366 
Fax +1 508 748 2543 
systems@ysi.com
SonTek/YSI 
+1 858 546 8327 
Fax +1 858 546 8150 
inquiry@sontek.com
YSI Environmental Gulf Coast 
+1 225 753 2650 
Fax +1 225 753 8669 
environmental@ysi.com
YSI Hydrodata (UK) 
+44 1462 673 581 
Fax +44 1462 673 582 
europe@ysi.com
YSI Middle East (Bahrain) 
+973 1753 6222 
Fax +973 1753 6333 
halsalem@ysi.com
YSI (Hong Kong) Limited 
+852 2891 8154 
Fax +852 2834 0034 
hongkong@ysi.com
YSI (Qingdao) Limited 
+86 532 575 3636 
Fax +86 532 571 0101 
ysiqd@ysiqd.com.cn
YSI Nanotech (Japan) 
+81 44 222 0009 
Fax +81 44 221 1102
nanotech@ysi.com
ISO 9001 
ISO 14001
Who’s Minding the Planet?, EcoSense, 
and Pure Data for a Healthy Planet are 
trademarks of YSI Incorporated. 
©2007 YSI Incorporated 
      Printed in USA 0107 W56-04 
pH100 Instrument Specifications
Temperature  Range  -10 to +120°C       
  Resolution  0.1°C 
  Accuracy  ±0.3°C ±2 digit
pH  Range  -2 to 16 units       
  Resolution  0.01 unit 
  Accuracy  ±0.1% ±2 digit
mV  Range  -1999 to +1250 mV 
  Resolution  1 mV 
  Accuracy  ±0.1% ±1 digit
Additional Technical Specifications
Operating range:
 Temperature:     0° to 50° C
 Relative Humidity:     up to 95% 
Water resistance     IP-65 water resistant, splash resistant
Size     70 mm width x 186 mm length (2.8 in. x 7.3 in.)
Weight with battery     430 grams (1 lb.)
ATC Probe     ermistor, 10kΩ / 25° C
Battery     One 9 volt included with purchase
pH temp compensation    Auto/Manual -10.0° C to 120.0° C
pH buffer recognition    (4.01, 7.00, & 10.01) or (4.00, 6.86, & 9.18)
pH calibration temp     0° C to 60° C
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 
Calibration back-up     Yes
Audio feedback     Yes, all keys
Autolock feature     Yes
pH100 Ordering Information
pH100  pH100 instrument
100-1  1-meter waterproof Y-cable with combo pH electrode and temperature
100-4  4-meter waterproof Y-cable with combo pH electrode and temperature
111-1  1-meter piercing tipped double-junction electrode
112-1  1-meter flat tipped double-junction electrode
110-1  1-meter cable with pH electrode
115-1  1-meter cable with mV electrode
130-1  1-meter cable with temperature (ATC) probe
pH100CC-01  Kit (pH100 instrument, 100-1 probe and cable, 180 hard-sided carrying case)
pH100CC-04  Kit (pH100 instrument, 100-4 probe and cable, 180 hard-sided carrying case)
160  pH 4, 7, 10 electrode simulator (ensures instrument performance)
180  pH100 carrying case, hard sided, form fitted foam insert
480  So, black carrying case with shoulder strap, vinyl
Y S I i n c o r p o r a t e d 
     Whoʼs Minding 
           the Planet?
®
For more information about this product, please call YSI at 800-897-4151. You may also send e-mail inquiries to 
ecosense@ysi.com or visit www.ysiecosense.com.