(e) Push button and read. Scale is 0 to 50,000 ppm. Each line is 1000 ppm. Be sure to use temperature
correction Table 2-12 if water temperature is less than 50°F (10°C).
e. TDS Meter Care.
(1) Keep TDS meter clean and dry when not in use.
Do not submerse meter in water. Do not get meter body or face wet when taking
If TDS meter does not work properly after installation of new battery, replace meter.
(2) If the meter reading is less than internal standard at maximum setting of appropriate adjusting wheel, the
battery may need to be changed. See Figure 2-18 and use the following procedure:
(a) Turn TDS meter upside down and remove bottom cover.
(b) Note position of battery (4) and battery cable (5).
Do not use mercury or alkaline batteries. Use of these batteries will cause inaccurate
readings. Refer to Appendix E for correct battery.
(c) Install a nine volt transistor battery to battery connector.
(d) Replace back of instrument.
2-8. COLOR TEST KIT (Figure 2-19). This test kit is used to check the color of the raw water at each new operating
site when the turbidity is less than 8 NTU, See paragraph 2-15.
Avoid prolonged or repeated skin contact with the color solution. Wash with soap and
water. In the event of eye contact, wash eyes for 15 minutes using the eyewash.
a. General. This test is made by comparing the color of a measured amount of the raw water with an identical
amount of color-free potable water to which an accurately measured amount of standardized color solution has been
added. The readings are made by looking down through the column of liquid.
b. Procedure, Use of color test kit.
(1) Fill a cup with raw water and let it sit for 15 minutes. Then slowly fill one color column to the top mark with the
raw water to be tested.
(2) Fill second column with potable water.
(3) Place the two columns side by side and note the difference of color.
Keep track of how many times the color solution has been added to the potable water
(4) Use the eye dropper and draw color solution up to the 0.5 ml line. Add the color solution to the potable water
column. Mix contents by shaking with thumb over open top of column.
(5) Look down through both columns and compare. If the color in the raw water column is greater than the potable
water column, repeat step (4), If not, proceed to step (6).