Thermo Products USDT2004 manual Start, Alarm, Rkty

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START

Starts pump at pre-set insolation (solar radiation intensity)

ALARM

Enables/Disables protection functions

BTU

Energy calculation and setting

S ensor Designation – USDT 2004 accepts two different sensor types or a reference value . User can program a constant reference temperature instead of a sensor output. The factory-preset sensor is the thermistor (KTY 10) type. The KTY 10 tank sensor,

white wire, should be used in a conditioned environment and will not be permanently damaged up to 360 oF.

Selection:

S1 Sensor 1 (collector outlet) selection

S2 Sensor 2 (collector inlet) selection

S3 Sensor 3 (tank) selection

Designation:

PT PT 1000 sensor (1000 O at 0 oC, not available in US market)

KTY Thermistor sensor (2000 O at 25 o C)

250250 oF reference temperature

- 4 - 4 oF reference temperature

Sensor wires can receive electromagnetic pulses, which can result in a wrong temperature reading. The USDT 2004 reads sensor values every 50 ms. It can bundle several readings and process their average.

AV 1 Sensor 1 average

AV 2 Sensor 2 average

AV 3 Sensor 3 average

The numbers of samples can be programmed from 4 to 20. The impedance characteristics of sensors temperature dependencies are represented in the following table:

T

0

10

20

25

30

40

50

60

70

80

90

100°C

R(KTY)

1630

1772

1922

2000

2080

2245

2417

2597

2785

2980

3182

3392 Ω

Frost and overheating protections - Pump operation can be manipulated by the user in both collector stagnation and frost conditions. The set-up is possible in System Guard,

SGUARD, domain.

Overheating protection – The Circulation pump may not be powerful enough to circulate the heat transfer fluid in the solar loop with air pockets. User can program the pump to stop at a desired maximum collector temperature, shown by ? symbol, to protect the pump. The USDT 2004 will take over the normal operation after the temperature decreases to an acceptable working temperature, shown as =. This feature is disabled at 299 oF set point.

Frost Protection – Frost protection in the sun-belt region is provided by circulating water in the solar loop when freezing conditions exist. Regardless of the temperature difference ? T, the

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Contents Usdt Installation and User’s Guide Control unit has the following functions IntroductionFollowing sa fety precautions are strongly recommended InstallationPage Page Menmode is for use in advanced applications only. See P.9 GAL Flow rate gallon/h Energy collected in kWhDiff ?1 Hysteresis BandwidthDesignation SelectionLLP BTUOUT SENRkty AlarmStart INS EnablDisab SensOK Circ No CircIncorrect display of temperatures Malfunction, but realistic temperature values