Hydrotech ZS Consulting

Water quality monitoring equipment, Hydrotech, Hydrolab, YSI, In-situ, Eureka, EXO, Sondes, Multiprobes, Sensors, Monitoring equipment, Hydrolab repair, YSI repair, Nitrate, Nitrite, pH, Dissolved Oxygen, Turbidity, Conductivity, Salinity


Perfect multiprobes for a combination of spot checking and unattended deployments. Use with any PC, SVR4A®, NX8X and NX10 Handheld displays. 

Compact DS:

Is only 21.5” long and 2.6" in diameter, which makes it very portable.

Supports SDI-12 communication protocol. It will easily connect to a datalogger like Sutron®, Handar®, Waterlog®, or any datalogger that uses SDI-12.

Supports RS232 communication protocol. It will easily connect to a PC or PDA.

Internal Battery Pack. 8 AA batteries for unattended deployments when needed. 

Measures up to 10 parameters simultaneously:

  • Temperature in °C and °F
  • Conductivity in µS/cm and mS/cm
  • Salinity in ppt 
  • TDS
  • pH 
  • Dissolved Oxygen in mg/l and % 
  • ORP (Redox) in mV
  • Depth in meters or feet
  • Total dissolved gas “TDG” mmHg
  • Self clean Turbidity sensor 

Specs Compact DS:

  • Size: Outer diameter: 2.6” (6.6 cm)
  • Length: 21.5” (54.61 cm)
  • Weight: 3.8 lbs/1.7 kg. ( Fully loaded) 
  • Computer Interface: RS-232, SDI-12 and RS-485
  • Memory: 120,000 measurements
  • Operating Temperature: -5 to 50 °C
  • Maximum Depth: 225 m
  • Internal Battery Pack: 8AA 
  • The Temperature sensor is a 30k ohm variable resistance thermistor. (The temperature sensor is included with every Hydrolab sonde.)
    • Range: -5 to 50 °C
    • Accuracy: +/- 0.10 °C
    • Resolution: 0.01 °C

  • Optical Dissolved Oxygen sensor. Hach LDO sensor: 
    • Range: 0 to 20 mg/L
    • Accuracy: +/- 0.1 up to 8 mg/L ; +/- 0.2 above 8 mg/L
    • Resolution: 0.01 mg/L

  • The Conductivity sensor uses four graphite electrodes in an open cell design.
    • Range: 0-100 mS/cm
    • Accuracy: ± (0.5% of reading + 0.001 mS/cm)
    • Resolution: 0.001

  • The pH sensor uses a glass bulb and refillable reference electrode. 

  • pH:
    • Range: 0 to 14 pH units
    • Accuracy: +/- 0.2 units
    • Resolution: 0.01 units

  • ORP:
    • Range: -999 to 999 mV
    • Accuracy: +/- 20 mV
    • Resolution: 1 mV

  • Custom-made Pressure sensors with two range options.
    • Range: 0 to 25m or 0 to 100m
    • Accuracy: +/- 0.05 meters
    • Resolution: 0.01 meters

  • The Total Dissolved Gas (TDG) sensor uses a pressure transducer mounted behind a rigid gas-permeable silicone membrane to measure the amount of total gaseous compounds dissolved in a liquid. Maximum water depth is 25 m.
    • Range: 400 – 1300 mmHg
    • Accuracy: +/- 0.1% of span
    • Resolution: 1.0 mmHg

  • The Self-Cleaning Turbidity sensor measures from 0 to 3000 NTU and includes a user-programmable cleaning system to remove any fouling or debris that could otherwise affect readings.
    • Range: 0-3000 NTU
    • Accuracy (compared to Stable-Cal): 1% up to 100 NTU, 3% from 100-400 NTU, 5% from 400-3000 NTU
    • Resolution: 0.1 NTU from 0-400 NTU; 1 NTU for >400 NTU
    • Temperature Coefficient: 0.05%/C

Most common questions and answers:

Q: Does the Compact DS use the same communication protocol as the Datasonde®? 

A: Yes. The Compact DS uses the same firmware as the Datasonde® with all its features.

Q: Can I use the Hydras 3 LT to communicate with the Compact DS? 

A: Yes.

Q: Can I use the Hydras 3L Pocket software with the Compact DS? 

A: Yes.

Q: Can I use my existing Hydrolab® cables to connect to the Compact DS? 

A:  Yes. The standard Compact DS comes with the standard Hydrolab® 6 pin cable connector.

Q: I do not like the standard Hydrolab® 6 pin cable connector, can the Compact DS be fitted with a YSI® type connector? 

A: Yes. The "Compact DS" can be fitted with an optional YSI® type cable connector with recessed pins for maximum ruggedness and it will work with your existing YSI® cables.

Q: Does the Compact DS have internal memory? 

A: Yes, it has enough internal memory for 120,000 measurements.

Q: Which batteries does the Compact DS use ? 

A:  The Compact DS is equipped with a 8 AA internal battery pack.  They are designed for short unattended deployments only ( one to four weeks  depending on the setup). 

Q: Does the Compact DS require internal batteries when used with the SVR4A®? 

A:  No, the Compact DS does not require internal batteries when used with the SVR4® display.

Q: Does the Compact DS require internal batteries when used with the NX8 or the NX10 handheld units? 

A: No, the Compact DS does not require internal batteries when used with the NX8 or the the NX10 handheld units.

Q: Does the Compact DS require external power when used with the computer ?

A:  No external power required when internal batteries are installed. 

Q: When connected to a Datalogger, can the Compact DS still log data internally ? 

A: Yes. The Compact DS can perform all the following tasks simultaneously: 

Communicate with a PC or Handheld unit via RS232 or RS422

Communicate to a datalogger via SDI-12 or RS232 

Log data to its internal memory up to 4 files at a time, even with overlapping dates

P.O. Box 5520

Round Rock, TX 78683  

1700 Bryant Dr. suite 103

Round Rock, TX 78664


Telephone: 512-846-2893

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