6.
Operation
Up to 5 sensors can be connected to the input contacts (always one sensor to one contact!).
The device can be connected with a computer equipped with serial interface RS232. Maximum 255
devices can be connected to one interface.
RTT 8 is equipped with 5 outgoing relays with switching contacts connected to the output
connectors.
At picture 1. the switching connectors have been shown in the power-off position. The condition of the
first three relays (P1, P2, P3) depends on the temperature of the sensors (K1, K2, K3, respectively).
The threshold temperatures TxH and TxL for each relay can be adjusted from the keyboard or an out-
side computer.
If sensor temperature exceeds TxH, relay will be automatically switched off. After the temperature has
dropped below TxL, relay will be switched on again. If the input sensor is short connected or has been
torn out, RTT8 reacts as if the temperature has been exceeded and switches the relay off.
Relay 4.
Functioning of the relay 4 depends on the operating mode set.
In the temperature control mode the relay operates identically to the first three ones (P1,P2,P3,). It
controls sensor K4.
In the maximum temperature control mode the device compares the highest value measured on the
sensors K1, K2 and K3 to the threshold temperatures T4H and T4L, switching relay 4 on or off
respectively.
In the timing mode the relay will be switched on after a desired period. The previously set time
interval is counted down after the testing procedures, initialised when power is on, have been
completed.
Relay 5.
Functioning of the relay 5 depends on the operating mode set.
In the temperature control mode the relay operates identically to the first three ones (P1,P2,P3,). It
controls sensor K5.
In the timing mode relay 5 is being switched off simultaneously with relay 3. Relay 5 will be switched
on after time delay set, counted down from the moment of switching on relay 3.
In the parallel mode relay 5 operates identically to relay 2.
Operation of the relays 4 and 5 is steered by the programme code, which can be modified from the
keyboard or an outside computer.
Relay 5
Relay 4
Display
X.7 X.6 X.5 X.4 X.3 X.2 X.1 X.0
K45=>00000000
X
.7 – not used
X.6 – switches relay 5 to parallel mode
X.5 – switches relay 5 to timing mode (time in min.)
X.4 - switches relay 5 to temperature control mode
X.3 – not used
X.2 – switches relay 4 to maximum temperature control mode
X.1 – switches relay 4 to timing mode (time in sec.)
X.0 – switches relay 4 to temperature control mode
Values X.7 – X.1 can be entered only as 0 or 1. Value 0 switches the respective mode off, whereas
value 1 switches it on.
Programming of the operating mode is being carried out by entering value 0 or 1 in the consecutive
fields. A blinking cursor will be visible on the display under the first digit possible to alter. (K45=> _ -
------ )
“_” indicates current position of the cursor
Any improper values of the programming code K45 will be automatically deleted.