LPGmass
12
Hauser
Potential equalization
Requirements
No special measures for potential equalization are required.
For devices intended for use in hazardous locations, please observe the guidelines in the Ex
documentation (XA).
Terminals
Transmitter
Spring terminals for wire cross-sections0.5 to 2.5 mm
2
(20 to 14 AWG)
Safety Barrier Promass 100
Plug-in screw terminals for wire cross-sections0.5 to 2.5 mm
2
(20 to 14 AWG)
Cable entries
• Cable gland: M20 × 1.5 with cable 6 to 12 mm (0.24 to 0.47 in)
• Thread for cable entry:
– NPT ½"
– G ½"
– M20
Cable specification
Permitted temperature range
• –40 °C (–40 °F) to +80 °C (+176 °F)
• Minimum requirement: cable temperature range ≥ ambient tempe20 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 Ω at 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
Shield
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
Comply with the maximum cable resistance specifications to ensure the operational reliability
of the measuring device.