Heliodyne Delta T Pro Installation Manual Download Page 7

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WIRInG foR aDDITIonal boaRD fUnCTIons

S O L A R H O T W A T E R

2.4. Additional Functions

2.4.0. Functions

The Delta-T Pro controllers can be wired to access several
additional functions as described below. Control reset and
manual operation of the relays is also addressed here.

2.4.1. thermostat Zone Detection

Household thermostats can be wired into 1 of the 4 spots on the
controller for detection upon close indicating a call for heat. There
is one pluggable insert for two connection pairs.

The contacts are not wetted and need to be supplied 24VAC
to detect a call for heat. In space heat mode, Relay 2 will be
energized if a zone calls for heat and the temperature read on the
set sensor is within the set limits.

Relay 3 can also be set to perform this function.

2.4.2. variable Speed current Output

A 4-20mA controlled current output is supplied to pumps for
variable speed operation when selected in the settings. The
principle of operation is to keep the temperature gain across the
collectors constant throughout the day and between 8°F and 15°F.
If there is not sufficient solar energy to collect, the pumps operate
at a minimum speed (provided a satisfactory differential). If there
is ample solar energy, the pumps operate at maximum speed.
Take care to preserve polarity. Wire the appropriate supply to the
pump’s AC input with Relay 1.

2.4.3. Pulse Flow Meter connection

If necessary, a pulse flow meters can be used in place of the use
of a grundfos VFS. The meter must be capable of producing a
square-wave pulse with a pull up to positive DC voltage of 3VDC.
The controller provides 10VDC supply to the meter. Ensure the
number of pulses are set in the settings.

2.4.5. Manual reset of Network Parameters

To reset the network parameters, place the removable jumper
stored at the left and middle pins of the JP5 location on the left
of the board, to the middle and right pins. With the jumper in
place, firmly press the reset button and hold for approximately two
seconds. Replace the jumper in its original location.

ZONE DEtEctION WIrING

cONtrOLLED cUrrENt WIrING

PULSE FLOW MEtEr WIrING

MANUAL rELAY OPErAtION

NEtWOrk rESEt

2.4.4. Manual Operation of relays
NOtE: Beginning August 2011, a switch has been added to the Pro
controller which eliminates the need of jumpers.

Often it is necessary to test the relays manually, or shut off the
relays should a problem occur. The Delta-T Pro offers a set of 6
pins for which to provide this functionality. The possible modes are
OFF, ON, and AUTO. The controller is shipped in AUTO mode,
with a removable jumper in the AUTO position. Turning the pumps
on requires an additional jumper; use the reset jumper at the left of
the board. This part of the board is low voltage (<5VDC).

NOtE: tHE FOLLOWING IMAGES IN SEc 2.4 HAvE tHE cONtrOLLEr BOArD rOtAtED SIDEWAYS

FIg. 2.4.1

FIg. 2.4.2

FIg. 2.4.3

FIg. 2.4.4

FIg. 2.4.5

PIns

JP5

JP6

JP5

ReseT

bUTTon