General Tips And Information - QTech SMS Lite 4G User Manual

General Tips and Information

The SMS Lite is over voltage protected by a 30-volt Zenner diode. Voltages greater than this
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will blow the internal 2A fast blow fuse. The supply voltage should be clean, continuous and
transient free.
To comply with the New Zealand and Australian wiring regulations the SMS Lite cannot be connected to any
external voltages exceeding 32 volts AC or DC. To connect to or control higher voltage equipment please consult a
DO NOT use Switch Mode Power Supplies (SMPS) with this product. The DC power supply used for this product
MUST have a grounded negative or be a "linear" transformer-based plug pack. The reason is that the antenna,
programming port and external connections can provide exposed earth points and the SMPS can impose an AC
Suitable cost-effective plug packs are available from QTech including P/N PD5412, PD5413 & PD5414.
The reliability of all cellular products is dependent on good signal strength. Before deciding
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on the Telco to choose, please check coverage. We suggest that a cellular phone is taken to
site, to check the signal strength, i.e. how many "bars" are displayed.
The supplied stub antenna (P/N PD9230) should be suitable for locations with good cellular
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coverage (full bars) and where the SMS Lite is in a non-conductive enclosure (e.g., plastic).
Other external mounting antenna options are also available; contact your equipment
supplier or QTech Data Systems Ltd for more details.
Inputs are connected to suitable mechanical switches, contacts and other closure devices.
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An input is active or ON when the input switch is closed and inactive or OFF when the input
switch is open.
Only mechanical switches or mechanical closure devices should be connected to the inputs. DO NOT connect
The relays are internally protected by solid state snubbers for operating with inductive
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loads.
SMS Lite 4G– User Guide
Registered Electrician.
voltage on the DC ground, which can lead to damage.
DO NOT operate the SMS Lite without an antenna connection.
external voltage or other electrical source to the inputs.
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