KROHNE OPTITEMP TT 51 EN - Manual (Page 15)

ELECTRICAL CONNECTIONS
4
15
TT 51 SERIES
www.krohne.com 09/2010 - 4000754201 - MA TT 51 R01 en
4.1 Safety instructions
4.2 Electrical connections of in-head transmitter
The input and output signals and the power supply must be connected in accordance with the
following illustrations. The transmitter is easy to install with the connection head installation kit.
To avoid measuring errors, all cables must be connected properly and the screws tightened
correctly.
DANGER!
All work on the electrical connections may only be carried out with the power disconnected. Take
note of the voltage data on the nameplate!
DANGER!
Observe the national regulations for electrical installations!
DANGER!
The transmitter is protected against polarity reversal. No damage will occur to the device if the
polarity of the supply voltage is switched. The output will then indicate 0 mA.
DANGER!
The TT 51 C / TT 51 R are optionally available in a non-incendive version for use in potentially
explosive atmosphere zone 2. For zone 2 applications a class 2 power supply placed in safe area
is needed. In other potentially explosive areas, the intrinsically safe versions must be used.
The TT 51 C (intrinsically safe) can be installed in potentially hazardous area zone 0, 1 and 2.
The TT 51 R (intrinsically safe) can be installed in potentially hazardous area zone 1 and 2 and the
input may be connected to zone 0.
The intrinsically safe versions must be supplied by an intrinsically safe power supply unit or
Zener barrier placed outside of the potentially explosive zone.
WARNING!
Observe without fail the local occupational health and safety regulations. Any work done on the
electrical components of the measuring device may only be carried out by properly trained
specialists.
INFORMATION!
Look at the device nameplate to ensure that the device is delivered according to your order.
Check for the correct supply voltage printed on the nameplate.