Endress+Hauser Proline Promass I 100 - Electrical Connection; Connection Conditions; Requirements for Connecting Cable

Electrical connection Proline Promass I 100 Modbus RS485
24 Endress+Hauser
7 Electrical connection
7.1 Connection conditions
7.1.1 Required tools
• For cable entries: Use corresponding tools
• For securing clamp (on aluminum housing): Allen screw 3 mm
• For securing screw (for stainless steel housing): open-ended wrench 8 mm
• Wire stripper
• When using stranded cables: Crimping tool for wire end ferrule
7.1.2 Requirements for connecting cable
The connecting cables provided by the customer must fulfill the following requirements.
Electrical safety
In accordance with applicable federal/national regulations.
Permitted temperature range
• –40 °C (–40 °F)...≥ 80 °C (176 °F)
• Minimum requirement: cable temperature range ≥ ambient temperature + 20 K
Power supply cable
Standard installation cable is sufficient.
Signal cable
Modbus RS485
The EIA/TIA-485 standard specifies two types of cable (A and B) for the bus line which
can be used for every transmission rate. Cable type A is recommended.
Cable type A
Characteristic impedance 135 to 165 Ωat a measuring frequency of 3 to 20 MHz
Cable capacitance < 30 pF/m
Wire cross-section
> 0.34 mm
2
(22 AWG)
Cable type Twisted pairs
Loop resistance ≤ 110 Ω/km
Signal damping Max. 9 dB over the entire length of the cable cross-section
Shielding Copper braided shielding or braided shielding with foil shield. When grounding
the cable shield, observe the grounding concept of the plant.
Connecting cable between Safety Barrier Promass 100 and measuring device
Cable type Shielded twisted-pair cable with 2x2 wires. When grounding the cable shield,
observe the grounding concept of the plant.
Maximum cable resistance 2.5 Ω, one side