Measuring Tds (Total Dissolved Solids); Option 1: Using A Tds Meter; Option 2: Using A Brix Refractometer; Option 3: Manually Checking Volume Ratio - Cornelius Nitropro Mini Service And Preventative Maintenance Manual

4.3.3.1 Measuring TDS (Total Dissolved Solids)

There are three methods that may be used to check/cali‐
brate the ratio setting of the equipment.
1. Using a TDS Meter
2. Using a Brix Meter/Refractometer
3. Manually Checking Volume Ratio
For each method, access the mix‐ratio control switches (Fig.
4‐3) by removing the splash panel. NOTE: Only one ratio
select switch is allowed to be On, with all others Off.

Option 1: Using A TDS Meter

A TDS meter measures the Total Dissolved Solids in a drink.
For coffee, it measures the level of extraction and can be
used to ensure that the correct mix ratio is achieved. If the
TDS target is known, a TDS meter allows for a simple process
to measure and ensure proper calibration.
1) Follow instructions for the TDS meter to ensure proper
calibration and zero setting prior to starting this process.
2) Follow steps 1‐5 in section 4.3.3 previously.
3) Using a straw, transfer a small sample of the finished
drink to the TDS meter lens.
4) Check the TDS value on the meter.
5) Adjust the unit ratio setting with the tuning buttons and
purge the system by dispensing a 16 oz. drink after each
adjustment.
NOTE: Since this method measures TDS, the 'UP' tuning but‐
ton will adjust TDS up, and the 'DOWN' button will adjust
TDS down.

Option 2: Using a BRIX Refractometer

A Brix refractometer is used to measure the sugar content in
aqueous solutions. This method may not apply to all coffee
concentrates, but many concentrates have natural sugars
that allow a Brix refractometer to be used. In order to use
this method, the target Brix value must be known for the
coffee concentrate.
1) Follow instructions for the Brix refractometer to ensure
proper calibration and zero setting prior to starting this pro‐
cess.
2) Follow steps 1‐5 in section 4.3.3 previously.
3) Using a straw, transfer a small sample of the finished
drink to the Brix refractometer meter lens.
4) Check the Brix value on the meter.
5) Adjust the unit ratio setting with the tuning buttons and
purge the system by dispensing a 16 oz. drink after each
adjustment.
NOTE: Since this method measures Brix, the 'UP' tuning but‐
ton will adjust Brix up, and the 'DOWN' button will adjust
Brix down.
© 2019, Cornelius Inc. All Rights Reserved

Option 3: Manually Checking Volume Ratio

Additional Supplies
• Weighing scale
Following steps explain measuring the water‐to‐ coffee‐con‐
centrate ratio using weight.
NOTE: Weight can be substituted by volume if a weighing
scale is not handy.
1) Follow steps 1‐5 in section 4.3.3 previously.
2) Pull the Left & Right Tap Handles for 10 seconds one after
the other to make sure coffee is dispensing.
3) Set 10 seconds timer.
4) Pull the Left Tap Handle for 10 seconds to dispense the
coffee and weigh the product dispensed.
5) Divide #4 by the total parts to get the target coffee con‐
centrate dispense weight.
6) a) If the total dispense is 300 grams and desired ratio is
5:1, divide by 6 to get 50 grams concentrate target for a 10
second pour.
b) If the total dispense is 300 grams and desired ratio is
4:1, divide by 5 to get 60 grams concentrate target for a 10
second pour.
c) If the total dispense is 300 grams and desired ratio is
3:1, divide by 4 to get 75 grams concentrate target for a 10
second pour.
7) Turn off water to the unit.
8) Pull the Left Tap Handle for 5 seconds or until coffee is
darker and only concentrate is dispensed.
9) Set 10 seconds timer and dispense concentrate by pulling
the Left Tap Handle.
10) a) If weight is greater than #6 target, use the 'DOWN'
button on controller to slow the concentrate motor down.
b) If weight is less than #6 target, use the 'UP' button on
controller to speed up the concentrate motor.
11) Set 10 seconds timer and dispense concentrate by pull‐
ing the Left Tap Handle until target value from #6 is within
+/‐ 2 grams of target.
12) Turn water on to unit.
13) Pull the Left Tap Handle for 10 seconds until coffee is
dispensed.
14) Pull the Right Tap Handle for 10 seconds until coffee is
dispensed.
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Nitropro Mini Service Manual
Publication Number: 548000106SER