Serial Dilution; Zero Point Calibration - palintest Macro 900 Operation Manual

Macro 900 Operation Manual
Part number: 250899
Description: 1, 5-Naphthalenedisulfonic acid disodium salt hydrate
(95% pure)
Supplier: Sigma Aldrich
Contact: www.sigma-aldrich.com
Be sure to handle chemicals with care and to read and comply with all
health and safety advice.
15.7.6.

Serial Dilution

10ppm Napthalene salt can be prepared either as a one or two step process
dependent upon the accuracy of the scales used.
One step process:
Weigh out 10.5mg of the recommended salt and add to 1L of deionized water in
a volumetric flask. Invert or mix until all salt has dissolved. This gives the Pt-2
10ppm stock solution required for calibration.
Two step process:
Step 1: Weigh out 1.05g of the recommended salt and add to 1L deionized
water in a volumetric flask. Invert or mix until all salt has dissolved. This gives
a 1000ppm stock solution.
Step 2: Transfer 10ml of the 1000ppm stock solution to a 1L volumetric flask
and top up with 1L of deionized water. Invert 10 times. This step results in a 1
in 100 dilution of the 1000ppm stock giving the 10ppm standard required for
Pt-2 calibration.
The dilute solution can be stored in a dark bottle in a refrigerator for up to five
days. After that time it must be discarded.
Important note:
naphthalenedisulfonic acid disodium salt, the readings given will be in μg/L
(ppb) naphthalene. In order to display readings with respect to a specific type
of refined oil, it is necessary to prepare a 10ppm solution of the target oil type
and use that to calibrate the probe in place of the naphthalene solution.
15.7.7.

Zero Point Calibration

To calibrate the zero point, follow these steps:
1. Fill a calibration bottle with distilled water, remove the storage cap from
the pH probe if fitted, wash the Probe in distilled water, then drop the
Probe in all the way. The Sleeve End Cap and Plug must be fitted.
Bang the Probe against the bottom of the bottle several times in order to
remove any air bubbles that may be clinging to the probe.
2. Switch the Macro 900 Meter on and wait until the temperature and Oil
readings are stable. If the Oil reading is very high, there are probably air
bubbles adhering to the lenses. Bang the Probe against the bottom of the
© 2013 Palintest Ltd.
When calibrating
www.palintest.com
the Refined Oil sensor with
Page 89 of 147
V3