Installation, Operation & Maintenance Parksafe Gas Detector
Rev: 9 10-20
8
Quick Tips
CONNECTION:
The best way to connect devices in a MODBUS RTU is a ‘DAISY CHAIN’ method.
MAXIMUM DISTANCE:
You may encounter problems when powering gas sensors beyond 500 yards from one control panel, in
this instance, contact your supplier.
TERMINAL RESISTANCE:
Signal communication issues may occur. To avoid this, terminating at each end of a chain may help the
quality of the data signal by turning on the 120ohm terminal resistor switches.
GROUNDING:
If you are encountering noise or irregular or abnormal problems with a Modbus link, the problem is likely
related to grounding, incorrect shielding or wiring main power next to Modbus wiring.
CABLES TO USE:
A shielded and twisted pair cable is used. The shielding can be of 2 types: braided [like a mesh of thin
conducting wires] or like a foil [consisting of a thin sheet of metal covering the twisted wires].
PROTECTION:
High concentrations of alcohol found in many products may damage, deteriorate or affect the gas sensing
elements of Detectors – such as; wine; deodorants; stain removers; thinners etc.
IDENTIFICATION:
Remember to individually ID each connected detector by configuring the ID switches on the circuit board.
Make a plan, map and/or note of the location of all connected detectors for tracing and locality purposes.
Wiring of different circuits shall be separated by means of routing, clamping or barrier!
All Class 2 wiring is to be installed within flexible tubing to maintain segregation between circuits!
Any damage attempting to remove the circuit board parts may void any warranty!
Do not remove the Gas Sensor Module when the detector is powered!
A shielded cable is used for all wiring!
