harvst Harvster, Руководство пользователя

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Water pump
If you have a water pump, it plugs into the middle-sized 2-pin connector on the control unit
(the large 2-pin connector is for power, and the smaller one is for the tank level sensor).
Water solenoids
The water solenoids are electronic taps, which determine which zone will be watered when
the pump turns on (or your hose is connected). The manifold wire is plugged into the three
pin connector on the control unit.
Tank level sensor
If you have chosen to use water from a tank, you’ll be supplied with a water tank level
sensor; which triggers an email and/or SMS message when your water tank runs low. The
sensor can be fitted to the built-in tank in a Harvster, or your polytunnel / greenhouse water
butt.
If you’re using your own tank or a water butt, drill a 3.5mm hole and push the sensor in.
The sensor is supplied with 1m of cable. Extension cables are available. The tank level
sensor plugs into the smallest of the 2-pin connectors on the control unit.
Heaters
If you have a mains powered unit, there will be three connectors on the left hand side. The
top two​ connectors are for heaters; zone 1 at the top and zone 2 below it. Into these
connectors you can plug either Harvst heated seed trays, or heater pads to put into a grow
tub. You can use up to four heaters per zone (unless you are also using grow lights, in
which case use the maximum power tables at the end of this guide).
You might want to set seedling trays at 20 °C to germinate peppers, and salad grow tubs at
15 °C, perhaps. The bigger the tub you try to heat, the slower it will heat up, and the more
heat will be lost at the same time as heat is being put in, so you have a lower achievable
maximum temperature. A single heater pad should be able to keep a large grow tub at
least 10 °C above ambient temperature (even when the outside temperature is freezing).
The pads can reach a maximum theoretical temperature of 40 °C, so it’s possible to get a
small amount of soil very warm.
Place your temperature sensors somewhere sensible so that they report the temperature of
the soil you’re heating, rather than the temperature of the heater pad. Keeping one or two
large tubs in the base of your Harvster warm will also keep the air temperature in the
Harvster to a reasonable level. Put any heated tubs on an insulating layer of wood, if
possible, to keep them off the cold ground.