Buhler Nivotemp NT64, Инструкция по установке и эксплуатации

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Bedienungs- und Installationsanleitung
Installation- and Operation Instruction
Nivotemp NT64 / Nivovent NV74
BX100020 05/2014 Art. Nr. 9032037
17
3 Installation and Connection
Installation of the device shall be performed by trained staff only, familiar with the safety requirements and
risks. Adhere to all relevant safety regulations and technical indications for the specific installation place.
!
DANGER
Toxic and corrosive gases
Protect yourself during maintenance against toxic / corrosive gases. Use
gloves, respirator and face protector under certain circumstances.
For direct tank top installation, insert gasket and immersion tube into the flange (dimensioned according to
DIN 24557, Part 2). Fix the device with the screws (included in delivery).
The float must move freely and must keep enough distance to the walls and to other equipment installed. If
the float had been demounted, make sure that the magnet inside the float is placed above the surface.
Check its position using a piece of iron.
The nominal supply voltage is 24 V DC. The device is connected via a connector on top. Please find the pin
assignment in the appendix.
The level contacts are designed as NO, NC or change over contacts and are mounted in customized
positions. The position as well as the contact function can be changed as described in chapter 3.1.
The switching logic assumes that the level switch is installed in an empty vessel, implicating that the
operating position is reached after filling the vessel.
Information on the correct operation of reed contacts in Bühler level switches
Based on their construction, reed contacts are very long lasting and reliable components. Yet the following
should be considered when using them:
Life of reed switches
The life of reed switches reed switches can be up to 10
9
cycles. This is reduces by high stress and / or
incorrect or the absence of protective circuits when switching inductive, capacitive or lamp loads.
It’s therefore important to ensure NEVER to exceed one or several of the maximum approved limits,
even temporarily, and to install a contact protective circuit for loads which are not purely ohmic.
Using test lamps when installing the devices is also prohibited, as these can temporarily allow too
much current to flow, which can damage the reed contacts.
In this case non-volatile testing
equipment should always be used.