2.1. Analog inputs: there are 2 inputs for PTC sensors with reinforced electric insulation for temperature monitoring;
2.2. A digital fire alarm input (the decision is made according to "closed/open" state, closed state corresponds to the running order, open state corresponds to the fire alarm signaling);
2.3. Two digital inputs for air conditioner fault sensors (if closed the air conditioner is faulty);
2.4. Main outputs:
- two-way break-before-make relay output for the 1st climate device control - 8A 250V at cosφ=1;
- a normally open relay output for the 2nd climate device control - 8A 250V at cosφ=1;
- a normally open relay output for the electric heater control - 8A 250V at cosφ=1;
- an opto-relay output to start the alarm signaling - 100 mA ~AC or =DC;
2.5. Temperature resolution - 0.1 ° C;
2.6. Nominal supply voltage: one-phase voltage is 220V/ 50Hz or three-phase voltage is 380V/ 50Hz;
2.7. Operating voltage: 160V - 330V;
2.8. Power consumption is no more than 5Wt;
2.9. Enclosure: IP40;
2.10.Terminal block enclosure: IP20;
2.11. Operating temperature: -10 °C to +55 °C;
2.12. Storage temperature: -45 °C to +75 °C;
2.13. Weight is no more than 0,3kg;
2.14. Mounted on the standard 35 mm DIN-rail;
2.15. Mounting position is arbitrary.
2.16. Operating controls and the dimensions of the device are shown on fig.1.
3.1. Connect 1st air conditioner, 2nd air conditioner,
electric heater, fire alarm sensor, alarm signaling and temperature
sensors according to fig.2.
3.2. Plug-in the MCK-301-2.
3.3. Power ON and set required operation modes according to the table 2.
Note. Button "▲" - UP in the text, button "▼" - DOWN in the text.
Fig. 1. MCK-301-2 front panel, indications and buttons diagram.
Fig. 2. The MCK-301-2 connections to the three-phase mains supply.
At the initial state the MCK-301-2 indicator displays the current indoor temperature as the average value of the temperature sensor ¹1 and the temperature sensor ¹2. On one of the temperature sensors fault the indicator shows the temperature measured by the serviceable sensor and an error code for the faulty temperature sensor.
The controller provides three control levels:
4.2. Keyboard locking level
Only viewing of the following parameters is available on this level:
- temperature setting, SP;
- temperature of the first temperature sensor, tS1;
- temperature of the second temperature sensor, tS2.
To view parameters one needs to press simultaneously the DOWN
and the UP buttons, the parameters scrolling is performed by the DOWN
and the UP buttons, to access a parameter it's necessary to press the
SET button.
When the keyboard is locked any button pressing (except simultaneous the UP and the DOWN buttons pressing) makes to appear the LOC label on the indicator. To unlock the keyboard the SET button is pressed. The "SET" LED lights up, and label "0" is blinking on the indicator. By the UP and DOWN buttons user enters a password digit from 1 to 9 and presses the DEF button. If the password is correct, the keyboard is unlocked. If after the keyboard unlocked no button is pressed during 16 sec and the lockage setting is not released by user, the keyboard is relocking.
4.3. User level with keyboard unlocked
This level allows:
- to change and to view the user level parameters;
- to view the adjuster level parameters.
To view and to change the user level parameters one needs to press the SET button, then "SET" LED will glow. Parameters scrolling is performed by the DOWN and UP buttons, to access a parameter one needs to press the SET button, parameters changing is effected by the DOWN and UP buttons, to set the parameter and go back into the MENU one needs to press the DEF button, going back to the menu without parameter setting is effected by the SET button. If no button is pressed during 16 sec the MCK-301-2 goes into the initial state.
4.4. Adjuster level
To access the adjuster level one needs to press and hold down SET button for 5sec. If the level is protected by a password, the label PAS appears on the indicator. Then press the SET button again. The "SET" LED lights up and the label "000" starts blinking on the indicator. Step-by-step enter three digits (from 1 to 9) of the adjuster password, pressing the DEF button after each digit has been entered. If the password is incorrect, the PAS label lights on (S is blinking), and the MCK-301-2 goes back to the initial state in 16 sec, otherwise the first parameter of the adjuster menu appears on the indicator.
Parameters scrolling is performed by the DOWN and UP buttons, to access a parameter one needs to press the SET button, parameter changing is effected by the DOWN and UP buttons, to set a parameter and go back into the menu one needs to press the DEF button, going back to the menu without parameter setting is effected by the SET button. If no button is pressed during 16 sec the MCK-301-2 goes into the initial state.
On the adjuster level the access to any user level parameter can be inhibited or permitted by simultaneous the SET and DOWN buttons pressing. If the access is inhibited a point indication appears on the right digital indicator when one is viewing the parameter value.
5. The MCK-301-2 modes of operation
5.1. The controller provides the following modes of operation:
- thermostat conditions;
- alarm conditions;
- diagnostic conditions.
5.2. Thermostat conditions
If two air conditioners are connected to the MCK-301-2 and the parameter nCo=2. the air conditioners are working in such mode of operation as "a main air conditioner - a stand-by air conditioner". The ttC parameter specifies the operating time for each air conditioner. After
the time has expired the other air conditioner starts working.
5.2.2. Parameters SP (electric heater cut-out temperature), and t_H (electric heater cut-in temperature) specify the indoor temperature conditions.
If the indoor temperature is below t_H, the electric heater is ON and it will operate until the indoor temperature exceeds Set Point.
If the indoor temperature exceeds the programmable SP+tC1 parameter, the air conditioner that considered to be the main one at the moment is ON and it will operate until the indoor temperature drops below Set Point.
If the indoor temperature exceeds SP+tC1+tC2, the stand-by air conditioner is ON and it will operate until the indoor temperature drops below Set Point.
EXAMPLE. According to factory settings SP=18, t_H=3,
tC1=4, tC2=3:
- lower temperature threshold is SP-t_H=18-3=15 (electric heater ON-temperature is 14, 9 C);
- the first upper temperature threshold is SP+tC1=18+4=22 (cut-in temperature of main air conditioner is 22,1 );
- the second upper temperature threshold is SP+tC1+tC2=18+4+3=25 (cut-in temperature of stand-by air conditioner is 25,1 ).
5.3. Alarm conditions
5.3.1. If both temperature sensors are faulty the two electric heater relays are off, the indicator sequentially shows temperature sensor fault codes, Erd code and the alarm goes off.
5.3.2. In the thermostat conditions the controller performs the indoor temperature monitoring and signals if the temperature goes outside the preset range.
If the indoor temperature exceeds user-preset temperature (HAL parameter) the indicator shows A1code and the alarm cuts-in.
If the indoor temperature is below LAL parameter the indicator shows A2 code and the alarm cuts-in signaling that the minimum temperature is reached. The alarm system will cut-out when the indoor temperature exceeds LAL+LLS value.
To disable premature alarm trippings for temperature tAO and PAO parameters are used. tAO is alarm tripping time delay for temperature (in minutes) and PAO is alarm tripping time delay for temperature after power has been applied (in hours).
5.3.3. If air conditioner safe operation control is allowed (dAc=1) the faulty air conditioner is OFF and the stand-by air conditioner is ON. On return the faulty air conditioner to normal operating conditions the MCK-301-2 reverse the air conditioners.
5.3.4. If the fire alarm goes off (the 5,6 contacts open), electric heater relays cut out and the Fir code is displayed on the indicator.
5.3.5. All fault state codes are displayed on the digital indicator according to the Table 1.
5.3.6. If any of faults referred to above occur the controller triggers alarm system (the 16,17 contacts open).
NOTE: If several faults take place simultaneously the fault codes are displayed on the MCK-301-2 indicator sequentially one after another.