Datasheet
Door Heater Controller with 3 x Triac Outputs
DOR / DIN / 3T / ...
Main Features Controls entrance Overdoor Heaters Scheduled Control Based on Outside Temperature Several variants for different plant configurations DIN rail mounting

Description of Features

General

This controller is derived from the SeaChange range of Fan Coil Controllers but has been specifically adapted for control of Door Curtain Heaters.

Control functions

The controller must be registered to a Zone Controller and uses the [Heat%] & [Cool%] and/or Occupancy state to define when it should run. Setting OCCO so the Curtain Heater only runs during the occupied period is supported, provided SPTY is 0-2.

Two distinct modes of operation are provided based on the value of SPFC (C1).

Scheduled control based on External Temperature

This mode is selected if the occupied setpoint SPFC (C1) is set to zero, NB to prevent overwriting from the Master Zone set SPTY=2, this is the default setting.

The controller calculates its output levels, heat and cool, based on the value of the external temperature. If a temperature sensor is fitted to the controller then this is used as a measure of external temperature, e.g. Mall corridor temperature, otherwise the system 'outside temperature' is used.

Four configuration variables setup the schedule for calculating the heat and cool outputs.

OMXC outside temperature for maximum cooling
OMNC outside temperature for minimum cooling
OMNH outside temperature for minimum heating
OMXH outside temperature for maximum heating

If the external temperature lies between OMNH and OMNC then the door curtain will be off. As the external temperature varies between OMNH and OMXH the heat demand will vary between 0 and 100%., similarly for cooling using OMNC and OMXC. If the external temperature is greater than OMXC then maximum cooling is produced, if less than OMXH then maximum heating is produced.
The control strategy ensures a differential of at least 5 degrees between OMNC and OMXC and between OMNH and OMXH.

If the multi-speed fan driver is selected the Fan Speed is calculated by extending the heating or cooling demand schedule on above 100%. For example if OMNH is 20 and OMXH is 10, the fan speed will be scheduled from 0% (one stage will run) to 100% as the external temperature falls from OMXH 10C to OMXH-(OMNH-OMXH), i.e. 0C. Similarly for cooling.

Vestibule Control

If the Occupied setpoint SPFC is non zero, then the controller provides temperature control based on a connected room temperature sensor. In this mode the setpoint can be supervised from a Zone Controller by setting (SPTY=1), if desired the vestibule temperature setpoint can be offset using either the setpoint trim SPTR or by setting the setpoint deadband SPDB to be particularly wide. In addition the user can be provided with local adjustment using the external wall mounted trim pot.

The controller will still switch off (non occupied) if the outside temperature (now obtained from the network) is between OMNH and OMNC as in the previous mode.

Cooling control is only provided if the outside temperature is above OMNC, the cooling setpoint used is SPFC plus trims and deadband as for a standard Fan Coil.

Fan Speed control is provided in the same way as a standard Fan Coil Controller, using the highest of heat demand or cool demand to increment (or decrement) the fan speed. Note fan speed control can be provided when in cooling even when no cooling driver is declared.

Interlocks

A single parameter for each driver type is provided which sets up the on delay or run on time for the fan or pump.

Typically negative values will be used for wet batteries to provide start up protection against frost and positive (run on-) values would be used with electric heating batteries.

The same features are available for cooling using CDLY.

The selection of OCC or OSS is now made by setting OCCO to 1 on controllers where the control is only required when the building is in occupation. The default is for control during OSS and OCC.

Frost Protection

This is defined with a config parameter FRPT and it defines the controllers action when it receives a 'frost alarm' from the boiler controller.

Alarms

The controller supports sensor fail SENF alarm, this is raised if the sensor fails and the controller is in a mode which requires the sensor. The Input Mode INMD can also be set up to generate an alarm for either a short or open circuit on terminals 3-4 'temp a'.

Alarm mode and Alarm State config variables have been added to the config variable list.

Alarm State ALST determines which input state 0 (open) or 1 (closed) is considered to be the alarm condition when using external input for the alarm as set by INMD.

Commissioning

Manual Mode

Holding down override button selects manual, status led flashes, initially this just sets 'occupied' and the controller will control to the occupied setpoint if a sensor is connected. The next press on the override button selects manual heating, the temperature led shows red, if the controller has a pot fitted this can be used to set the output level, otherwise full heating is selected. A further press on override gives manual cooling, temperature led shows yellow, again the pot if fitted controls the level of the output. A further press cancels manual and returns the controller to auto.

From Doorway, manual can be selected using the auto/manual syntax, e.g. W1(S)/AUTO/MANUAL/10/12/W2(S) - see Doorway Help files for more information. When the manual mode is selected 'ON' the controller output will follow the value set on config parameter MANL. 0-100% is heating, -100-0% is cooling.

Doorway codes

Like Fan Coils, Door Heater Controllers are addressed with [Zn] where n is the Zone number 1-200.

Options and Product Codes

Door Heater Controller

DOR / DIN / 3T / [driver option]

Driver options

SC Controls Ltd

PO Box313
Wadhurst
East Sussex
TN5 6JL

phone 08707 606040
fax 08707 606041
e-mail seachange@sccontrols.co.uk
http:// www.seachange.co.uk