Hach 1735 TRO, Hazardous Location Installation Manual, Page: 6 / 46

Figure 1 Electrical connections at the instrument
Install the associated apparatus
An associated apparatus limits the power parameters to the device that is located in the hazardous
area.
1. Install the associated apparatus in a non-hazardous environment.
2. Obey all requirements in the control drawings. Obey all codes and regulations for connection to
the instrument in a hazardous location. Refer to
Figure 2 on page 8.
Intrinsic safety entity concept
This instrument is approved for installation under the intrinsic safety entity concept. The entity
concept specifies:
• The maximum amount of energy available from each output
• The maximum amount of energy tolerable at each input for instrument safety
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