Hach 1735 TRO, Hazardous Location Installation Manual, Page: 5 / 46

Hazardous location installation
D A N G E R
Explosion hazard. Any installation or configuration that is not specifically shown on the control
drawings is not allowed. In all cases, the local authority with jurisdiction will make the final installation
decision.
This instrument is listed as intrinsically safe for Zone 1, Group IIC hazardous locations. Circuits within
the instrument cannot produce a spark or thermal effect that could ignite a mixture of flammable or
combustible gases. It does not mean that the instrument is explosion-proof. If all safety precautions
are not obeyed, or if the equipment is not installed correctly, there is a potential for explosion. Be
sure to review all safety precautions and installation instructions throughout this manual before
installation.
Intrinsically safe installation requirements
Installation of this equipment must obey local electrical code requirements as shown in the
hazardous location control drawings. Installation is subject to final approval by the authority that has
jurisdiction.
Hazardous location control drawings
D A N G E R
Explosion hazard. Do not connect or disconnect electrical components or circuits to the equipment
unless power has been removed or the area is known to be non-hazardous.
Obey the control drawings provided. Refer to Figure 2 on page 8. Obey all codes and regulations
for connection to the instrument in a hazardous location.
Install the instrument
W A R N I N G
Explosion hazard. In hazardous locations, friction between surfaces can generate sparks that can
cause an explosion. Make sure that no friction is possible between the instrument and any surrounding
surfaces.
W A R N I N G
Unused cable glands must be plugged. Use 9-mm plugs for small glands and 15-mm plugs for large
glands.
For hazardous locations, an acceptable associated apparatus must be installed outside of the
hazardous area.
For analyzer installation, refer to the
1735 TRO Analyzer User Manual.
Electrical installation
Electrical installation in a hazardous location
D A N G E R
Explosion hazard. Connect the instrument only to intrinsically safe associated apparatus that provides galvanic
isolation.
For installation in hazardous locations, install the associated apparatus with the appropriate entity
parameters between the instrument and any external circuit.
Electrical connections
Figure 1 shows the electrical connections.
English 5