ALCO EC3-33x, Руководство пользователя

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EC3-33x Coldroom Controller with EX5
User Manual
EC3-33x
A.6.5.063E - Rev 4
21
Emerson Electric GmbH & Co - ALCO CONTROLS - Heerstr. 111 - D-71332 Waiblingen - Germany - Tel.: ..49 (0) 7151 509 0 - Fax: 49 (0) 7151 509 200
Superheat Object
The superheat object is responsible for the superheat function. If the object is disabled, the valve will be closed. No network variable
updates will be performed, the object will not react on any input network variable update. Object status information is send by the
nvoStatus variable of the node object. If the object has an alarm condition, the alarm bit “in_alarm” of the status structure plus the
additional alarm bits like “unable to measure” for sensor failures, “out of limits” for 100% valve opening and “locked out” for external
alarm condition will be set. If the object is in manual control, the “manual control” bit is set. If the superheat set-point should be
overwritten by an external device, the “in override” request must be send to the object. These mode is indicated by the “in override”
bit of the status structure.
Network Variables
Variable Type Name Type Meaning
SNVT_lev_percent nvoValveOpening O Current opening of the expansion valve
SNVT_evap_state nvoEvapState O Current status of the superheat object
SNVT_temp_p nvoEvapInTemp O Currently used coil in temperature of the superheat object
SNVT_temp_p nvoEvapOutTemp O Currently used coil out temperature of the superheat object
SNVT_switch nviForcedValve I Manual control of the valve output
SNVT_temp_p nvoSuperheatRef O Currently used superheat set-point
SNVT_temp_p nviSuperheatRef I External superheat set-point, only in use when object is in override
SNVT_temp_p nvoDeltaTemp O Calculated superheat from coil out – coil in or coil out – saturation
temperature calculated from saturation pressure
SNVT_press nvoPressure O Saturation pressure output
SNVT_lev_disc nviSystemFailure I Input to lock the controller, ST_ON = valve closed and controller
locked
SNVT_state nvoEvapStatus O Detailed object status
UNVT_EVAPORATOR nciEvapCnfg C Superheat object configuration structure
The network variable from type SNVT_temp_p will have an value of 0x7FFF in case of an sensor failure or if no data was read from
the sensor input.
The network variable “nvoEvapStatus” is a bit fields and will represent the current status of the superheat object.
Bit No. Description
0 0 = Controller off, 1= Controller on
1 0 = no cooling, 1 = cooling
2 0 = no temperature modulating , 1 = temperature modulating
3 0 = fixed operation, 1 = adaptive operation
4 0 = automatic mode, 1= manual mode
5 0 = no MOT, 1 = MOT active
6 1 = Battery failure
7 1 = System failure
8 1 = Emergency operation
9 1 = no Refrigerant flow
10 1 = Evap. in sensor failure
11 1 = Evap. out sensor failure
12 1 = Pressure sensor failure
13 1 = Media sensor failure
14 1 = Air temp sensor failure
15 1 = 100% valve opening