UNISENSE Hydrogen Sulfide Sensors SULF User Guide

: June 3, 2024
: UNISENSE

Table of Contents

important! Test sensor upon receipt
USEFUL TOOLS
References
Read User Manual Online (PDF format)
Download This Manual (PDF format)

UNISENSE Hydrogen Sulfide Sensors SULF

important! Test sensor upon receipt

This sensor has been successfully tested prior to shipping, however some sensors suffer from rough transport at ion. Therefore, it is important that you test the sensor upon arrival.

REPLACEMENT OF DEFECTIVE SENSORS

Unisons will replace t he sensor if it does not meet t he specific at ions below, provided that:

A test is performed upon receipt without breaking the seal (Note! No seal on MR- sensors for testing purposes)
The complaint is given to Unisons within two weeks,, from receipt of the equipment.

GUARANTEED LIFETIME

Unisons guarantees the SULF sensor a minimum lifetime of 6 months on condition of correct storage and use according to the manual.

INDIVIDUAL SENSOR CALIBRATION IS REQUIRED

Our sensors are handmade and as the sensor signal relies on the exact geometry of the sensor tip (micrometer scale), some variant ion must be expected. Complete linearity cannot be expected in the high concentration range (more than 300 µM H2S). The H2S sensitivity decreases over time (not uniformly) no matter if the sensor is in use or stored.

SIGNAL AMPLIFICATION

Unisons SULF sensors should be connected to a Unisons amplifier such as a Uncap series instrument or the Field Microsensor Multimeter

STANDARD HYDROGEN SULFIDE SENSORS ARE FUNCTIONING CORRECTLY IF (AT ROOM

TEMPERATURE):

The 90 % response time is wit hint he specified range (see table below)
The zero signal is less than 25 % of the signal in a 50 µM H2S calibration solution (see the table) and maximum 25 mV.

| SULF- 10| SULF- 25| SULF-m 50| SULF- 100| SULF- 200| SULF- 500| SULF- N| SULF- NP| SULF- MR| SULF- 50LR| SULF- 100LR| SULF- 500LR| SULF- NPLR
---|---|---|---|---|---|---|---|---|---|---|---|---|---
90 % response time (in sec.)| <10| <10| <10| <15| <15| <15| <15| <15| <15| <15| <15| <15|

<15

Zero- signal less than

| 15 mV| 15 mV| 15 mV| 15 mV| 15 mV| 15 mV| 15 mV| 15 mV| 15 mV| 20 mV| 20 mV| 20 mV| 20 mV

The sensor signal in PA is converted to an instrument signal in mV. The default setting of this Pre-Amp range is 1 PA = 1 mV. However, this can be changed by the user (see the instrument manual).

UNPACKING

Remove the grey shock-absorbing plastic net and inspect the sensor visually.
Leave the sensor in the protection tube for testing.

CONNECT THE SENSOR TO THE AMPLIFIER

The amplifier is automatically set up correctly when used with these instruments: Uncap series and Unisons in situ amplifiers.
For other amplifiers, set the polarization manually to +200 mV.
NOTE! Incorrect polarization may destroy the sensor

WAIT FOR THE SENSOR TO STABILIZE

The signal will be very high right after the sensor is connected and will decrease over time.
The period of decreasing signal will normally be at least 2 hours.
Once the signal is stable, calibration can be performed.

A typical decrease in sensor signal over time for a sensor that has just been plugged in.

CALIBRATE THE SENSOR

Place the sensor in sulfide free water to obtain the zero calibration point.
Prepare the sulfide solution according to the H2S calibration kit manual and inject the solution into the calibration cap.
For alternative calibration method, see the H2S Microsensor User Manual.

SULF-Sensor Injecting calibration liquid into protection tube using the calibration cap

APPROVE THE SENSOR

Compare the calibration points to the specifications given on t he previous page. If necessary, see Troubleshooting in the H2S Microsensor manual or contact support {see below),.

STORAGE

When not in use, store the sensor with t he protection tube mounted at room temperature. If the sensor is used regularly, keep it polarized and connected to the amplifier