KELCO T20, Инструкции по установке и программированию

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Electrical
All electrical work associated with the T20 must
be carried out by qualified electrical personnel
and all electrical work must conform to AS/NZ
standards and to local wiring rules. For mains
voltage applications we recommend the sup-
ply to the T20 be isolated by an RCD that has a
maximum trip current of 30mA.
WARNING
Introduction
The T20 timer is designed to directly control single-phase pump motors to 3.75kW.
No interposing contactor is required for such applications. If a supply neutral or
transformer is available, the timer can also be used to control 3 phase pump mo-
tors via an appropriate interposing contactor that has a suitable coil voltage.
The T20 timer requires a 220V to 240V AC 50Hz supply when operated from the
mains. It can also be operated from an 18 to 24V AC or DC supply by utilising the
low voltage active terminal LV and common neutral terminal N, see the included
wiring diagrams. When operated from a low voltage DC supply the terminals LV
and neutral N are not polarity sensitive. The T20 timer requires a stable supply
voltage in order to operate correctly. Pay particular attention to cable sizes, and
ensure cables are adequate for the specific pump motor load. This is particularly
important where long cable runs are to be used in the installation. If the voltage
drop associated with the starting of the pump motor is excessive the T20 will au-
tomatically reset and this may cause the pump to jog. Jogging can snap the main
spindle of a pump very easily, so please take all precautions to ensure the voltage
supply to the T20 is stable and that the current carrying capacity of the cable used
is adequate for the job.
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