6.5 Cooling system: Coolant specimen, analysis

Caution

Always fill the cooling system using an Antifrogen N/water mixture in the ratio of 44% to 56%

Never add any other coolant! Always ensure that the coolant is clean! Suitably filter the coolant before filling the cooling system! Take into consideration the general safety information and instructions when handling Antifrogen N (refer to Chapter 6.7)! If the filling level specified is exceeded then it is possible that the equalization reservoir will overflow!

The cooling medium should be analyzed at regular intervals. In doing so, the specified antifreeze protection should be guaranteed and it should also be checked that the specified quantity of inhibitors are present. Inhibitors are chemical agents in the cooling medium that act to prevent corrosion.

The cooling medium specimen should be taken from the equalization reservoir. The following steps must be carried-out: • Remove the overflow hose at the cover of the equalization reservoir

• Open the equalization reservoir cover

Warning

The cooling system may be under pressure! The cooling medium can reach temperatures of up to 60°C. Danger of burning! Always carefully and slowly open the cover of the equalization reservoir to ensure slow pressure equalization!

• Withdraw the required quantity of cooling medium (250 ml) using a suitable instrument

• Replace the amount of cooling medium withdrawn so that the liquid level remains at the correct level (also refer to Chapter 6.4)

• Re-close the equalization reservoir cover

• Re-attach the overflow pipe and correctly tighten the pipe clamp (3 Nm tightening torque)

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Caution

Ensure that all of the equipment and containers are clean! Other media or substances in the coolant specimen could interfere with the analysis! Carefully take into account general safety information and instructions when handling Antifrogen N (refer to Chapter 6.7)!

The specimen should be analyzed in a test laboratory or by the manufacturer of the coolant

Clariant GmbH, Werk Gendorf Division Functional Chemicals Frau Sieglinde Winkler, Bau 300 C 6/1 D-84504 Burgkirchen Tel.: 08679-7-3347 Fax: 08679-7-5085

The following properties should be tested:

Property Acceptance criterion

Antifreeze protection Ice slush formation at T ≤ -35°C

Anti-corrosion protection The specimen must contain a sufficient level of anti-corrosion inhibitors

If one or both of these properties is (are) no longer in the permissible range then the coolant must be completely replaced (refer to Chapter 6.7)

6.6 Cooling system: Checking the seals at the coolant liquid connections

All of the coolant connections must be checked to ensure that they are not leaking.

This is done by wrapping a white, dry and absorbent cloth around the connections and checking whether the cloth absorbs any cooling medium that may have leaked. Cooling medium that has leaked has a color ranging from bright yellow up to amber. If cooling medium has leaked, then the cause of the leak should be investigated and resolved.

6.7 Cooling system: Replacing the coolant

The Antifrogen N agent used in the DCC cooling system guarantees the required antifreeze protection when the DCC is operated at low temperatures. The inhibitors contained in Antifrogen N guarantee optimum anti-corrosion protection. These inhibitors have a limited life especially when they come into contact with oxygen. In order to guarantee the correct functioning of the cooling system, the complete

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coolant must be replaced at regular intervals. This allows the optimum antifreeze and corrosion protection to be achieved.

Caution

The coolant should not be replaced at temperatures < 5 °C. The reason for this is that the kinematic viscosity of the cooling medium at low temperatures increases significantly making it unnecessarily difficult to replace the cooling medium. The pumps may never be allowed run dry. If this happens then the sleeve bearings will definitely be destroyed. Approx. 63 l of cooling medium has to be replaced. Only use suitable coolant. When releasing the coolant coupling (coolant connection) a small amount of residual coolant can remain in the coupling. Suitable measures (absorbent paper, cloth, or similar) must be used to ensure that any remaining coolant does not run into the DCC.

Basic information on Antifrogen N

Antifrogen N is used as antifreeze and anti-corrosion agent for water-cooled converters. If the antifreeze no longer has the specified concentration then the mixture promotes corrosion (e.g. for surfaces with just a film of antifreeze). This is the reason that coolant that has leaked must be immediately removed.

Caution

Antifrogen N is corrosive. In addition, Antifrogen N that has leaked can cause shortcircuits. This is the reason that each time the cooling water connections are opened, the phase module must be carefully cleaned and especially the modules located below it.

Handling Antifrogen N involves the following working conditions:

• Your own personal protective equipment

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Warning

The following protective procedures must be carefully applied when handling Antifrogen N:

• Do not breathe in any vapor

• Keep away from foodstuffs and beverages

• Hand protection: Protective gloves

• Eye protection: Protective glasses

First Aid measures

• Immediately remove clothing that has come into contact with Antifrogen N.

• After skin contact: If Antifrogen N comes into contact with the skin immediately wash off with a lot of water.

• After eye contact: If Antifrogen N comes into contact with the eyes apply plenty of water and contact a doctor immediately.

• After swallowing: Get the person to vomit under the assumption that he is fully conscious. Immediately contact a doctor. • Otherwise, the regulations laid down in the EC safety data sheet according to 91/155/ECC for Antifrogen N and the generally valid First Aid rules must be carefully observed.

The coolant is removed from cooling system in the following steps:

• Remove the overflow hose at the cover of the equalization reservoir

• Open the cover of the equalization reservoir

Warning

The cooling system may be under pressure! The cooling medium can reach temperatures of up to 60°C. Danger of burning! Always carefully and slowly open the cover of the equalization reservoir to ensure slow pressure equalization!

• Remove the step protection plate above the fast release drain coupling at the lower end of the heat exchanger (radiator).

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• Drain the cooling liquid using the drain hose at the cooler until cooling medium no longer flows.

Caution

The cooler starts to drain immediately when the drain hose is inserted! This is the reason that a suitable container must be provided and the drain hose placed in this container before the fast release coupling is inserted!

• Release all fast release couplings at the modules.

• Connect the drain hose at the cooling medium intake hose of module A3 and drain until no cooling medium flows.

Caution

The coolant distribution immediately drains when the drain hose is inserted! This is the reason that suitable containers must be provided and the drain hose placed in this container before the fast release coupling is inserted! Even after the cooling system has been completely drained according to these Operating Instructions, small quantities of cooling medium can remain in the water distribution system. When continuing to work on the cooling system we recommend that you always have absorbent paper at hand so that this liquid can be quickly removed.

The coolant circuit is filled in the following steps:

The cooling medium is filled using filling equipment.

The fast release coupling of the water intake of module A3 is the filling point. • Connect the pressure hose of the filling equipment at the filling point

• Open the cover at the equalization reservoir

• Ensure that the drain hose has been removed from the heat exchanger

• Ensure that all of the coolant hoses and all hose clamps are in place and secured

• Connect the connector of the pump feed equipment to the coolant pump of the DCC.

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Caution

When filling the cooling system only use Antifrogen N / water mixture in the ratio of 44%/ 56%!

Never use any other coolant! Always ensure that the coolant is clean! Suitably filter the coolant before filling it! If dirty coolant is used to fill the cooling system then this can result in severe operational disturbances and can also destroy the DCC components!

• Power-up pump of the filling equipment

• Stop filling when the coolant level has reached the filling mark at the main heat exchanger.

• Turn off pump of the filling equipment

• Disconnect the pressurized hose at the filling location of the DCC

• Power-up the coolant pump of the DCC using the pump feed equipment and circulate the coolant

• Fill and circulate the coolant alternating until the level remains constant at the mark provided

• Then disconnect the filling equipment and pump feed equipment from the DCC and re-connect the coolant hose used as filling point with phase module A3. Re-insert connector X68 at the pump and latch into place.

• Close the cover on the equalization reservoir.

• Re-locate the overflow hose and correctly tighten the hose clamp (3 Nm tightening torque)

Warning

Carefully take into consideration general safety information and instructions when handling Antifrogen N (refer to Chapter 6.7)!

Disposing of Antifrogen water mixtures

There are several ways of disposing of Antifrogen water mixtures: The mixture is always disposed of in an incineration system; in addition, companies can also be contacted that specialize in recycling glycol water mixtures. You can request a list of glycol recyclers from the Clariant Company (www.clariant.de). Antifrogen water mixtures are bio-degradable (refer to the safety datasheet) and after prior discussion with the operating company can also be disposed of in a biological water treatment plant when the applicable regulations are complied with.

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