The document describes the Siemens Terminal Box Controller, which provides direct digital control for variable air volume HVAC systems. The controller can operate independently or as part of the APOGEE Automation System to control various HVAC applications. It interfaces with sensors, actuators, and the Portable Operator's Terminal for monitoring and configuration. Key features include PID control, unique control algorithms, HVAC diagnostics, and energy management capabilities.

1. Siemens
Terminal Box
Controller
(APOGEE
Automation
System )

2.  The Terminal Box Controller is an integral part of the APOGEE¥ Automation
System.
 The controller provides high performance Direct Digital Control (DDC) technology
for room temperature control in Variable Air Volume (VAV) systems.
 The Terminal Box Controller and related components provide a totally electronic
control system.
 The Terminal Box Controller can operate independently, stand-alone or networked
to perform complex HVAC control, monitoring and energy management functions
without relying on a higher level processor.
 The totally electronic approach to temperature control includes the following
features.

3. Features
 PID control of HVAC systems to minimize offset and maintain
tighter set point control,
 Unique control algorithms for specific applications,
 Reports airflow in CFM (l/s),
 HVAC diagnostics through communication with a Portable
Operator's Terminal at a room sensor or any field panel,
 Set points and control parameters assigned and changed using
the Portable Operator's Terminal,
 Electrically Erasable Programmable Read Only Memory
(EEPROM) used for storing set points and control parameters no
battery backup required,

4. Features
 Returns from power failure without operator intervention,
 Meets low duct static pressure requirements,
 Uses proven APOGEE Automation System DDC architecture,
 No calibration required, thereby reducing maintenance costs, and
 Separate minimum and maximum air volume setting for heating and cooling
modes.

5. Applications
 Operating independently, or as a part of the APOGEE Automation System, the
Terminal Box Controller can control a variety of Variable Air Volume (VAV) pressure
independent terminal box applications, including:
VAV Cooling Only,
VAV Cooling or Heating,
VAV with Hot Water Reheat (proportional),
VAV with Electric Reheat (one-, two-, or threestage),
VAV Fan Powered Series or Parallel with Hot Water Reheat, and
VAV Fan Powered Series or Parallel with Electric Reheat (one-, two-, or three-stage).

6. Description
 The Terminal Box Controller consists of a differential pressure transducer and an
electronic controller assembly.
 An Auto zero Module is available for mounting on the controller for those
applications where uninterrupted airflow is necessary.
 A Pneumatic Transducer provides for control of pneumatic damper and valve
actuators.
 Control algorithms are preprogrammed.
 The controller is ready to operate after selecting the application and assigning the
unit's controller address with the Portable Operator's Terminal
 If desired, the operator may use the Portable Operator's Terminal to adjust the air
volume set points in CFM (l/s), room temperature set points and other
parameters.
 The controller is designed for operation and modification without vendor
assistance.

7. Differential Pressure Transducer
 The averaging air velocity sensor (provided by the VAV terminal unit manufacturer)
sends an average air velocity measurement of the duct air velocity to the
controller.
 The air velocity sensor connects to the differential pressure transducer (which is
mounted in the Terminal Box Controller) and measures the average differential
pressure.
 The Terminal Box Controller converts this value to actual airflow in CFM (l/s).

8. Specifications
Temperature Range 48 F to 112 F (9 C to 45 C)
Measurement Range 0 to 4000 fpm (0 to 20 m/s)
Measurement Resolution r4 fpm (r0.02 m/s)
Measurement Accuracy
300 to 4000 fpm
(1.5 to 20 m/s)
r5% of actual reading
200 to 300 fpm
(1 to 1.5 m/s)
+12% to -15% of actual
reading
Repeatability r8 fpm (0.04 m/s)
*All specifications assume an unadjusted flow coefficient of 1.

9. Terminal Box Controller
 This controller provides all wiring terminations:
input/ output, system and local communication
and power.
 The cable from the room sensor connects to a RJ-
11 jack on the controller.
 All other connections are removable terminal
blocks.
 The controller assembly is mounted on a plastic
track that is mounted directly on the terminal box.
 An optional enclosure protects the controller
assembly.

10. Terminal Box Controller
The controller interfaces with the following external devices:
 Averaging air velocity sensor provided by VAV terminal unit manufacturers,
 Floating control valve and damper actuators,
 Temperature sensors (room, duct, immersion, and outside air),
 Portable Operator's Terminal,
 APOGEE Automation System,
 Digital input devices (dry contacts from motion sensors, alarm
contacts), and
 Digital output devices (fan, stages of electric heat).

11. Technical
Power Requirements Operating Range 18 to 28 Vac 50 or 60 Hz
Power Consumption 3.5 VA (Nominal) to 5.0 VA
(Peak) @ 24 Vac
(plus loads)
Inputs Analog 1 room temperature sensor
1 velocity sensor
1 set point (optional)
1 auxiliary temperature sensor
Digital 2 dry contacts
Outputs 6 DO 24 Vac optically isolated
solid state switches @ 0.5 amp
Controlled
Temperature
Accuracy, Heating or
Cooling
r1.5qF (0.9 C)

12. Technical
Dimensions 4-1/8" W x 7-3/4" L x 1-1/2" H
(105 mm x 197 mm x 38 mm)
Weight approx. 3 lbs. (1.35 kg)
Communications Remote LAN Trunk
Local Portable Operator's Terminal
Ambient Conditions Storage Temperature -20 F to 167 F (-29 C 75 C)
Operating
Temperature
32 F to 122 F (0 C to 50 C)
Humidity Range 10% to 95% (non-condensing)
Agency Listings UL Listing UL 916, PAZX,
UL 864, UDTZ
CSA Certified
FCC Compliance

13. Optional Accessories
 The optional Autozero Module is required when continuous operation
at occupied flow is required for an area.
 The Autozero Module is connected to the air velocity inlet ports of
the Terminal Box Controller and provides periodic recalibration of
the air velocity transducer without changing air volume being
delivered to a room.
 This recalibration ensures long-term precise airflow delivery.
Specifications
Power Consumption 1.5 VA @ 24 Vac max.
Dimensions 2-1/2" W x 2-1/2" H x 1"D
(64 mm x 64 mm x 32)
Weight 0.5 lb. (0.2 kg)

14. Pneumatic Transducer
 The PTS Pneumatic Transducer contains the transducers that provide
the signal conversion from electronic to pneumatic.
 The module is piped to the pneumatic actuator and wired to the
Terminal Box Controller.
 This transducer provides for accurate control of pneumatic actuators
for precise temperature and air volume control.
Specifications
Maximum Input Pressure 30 psi (207 kPa)
Air Consumption 0 SCIM
Power Consumption 4 VA @ 24 Vac max.
Dimensions 3-1/2" L x 2-1/4" W x 1-1/2" H
(87 mm x 57 mm x 38 mm)
Weight 9 oz (0.3 kg)

15. Terminal Box Controller Communication
 Up to 32 Terminal Box Controllers or other Terminal Equipment
Controllers can be connected to each of the three field panel LAN
trunks.
 Communication with the Terminal Box Controller can be initiated
from any system field panel on the system network.
 The system network does not require additional hardware to connect
Terminal Equipment Controllers.
 When Terminal Equipment Controllers are wired to a field panel,
features such as energy management programs, alarm reporting,
centralized control, modification of the system database, system-
wide troubleshooting, and the global commanding of devices are
available to them.

16. Portable Operator's Terminal
 The DOS-based laptop computer serving as the Portable Operator's
Terminal can communicate with Terminal Box Controllers or any
field panel.
 The terminal connects to the controller, the room temperature
sensor associated with the Terminal Box Controller or field panel.
 The terminal can be used to remotely adjust air volume settings or
temperature set points, to troubleshoot and start-up the system.
 When connected to the RS-232 port of a field panel, the terminal
provides system-wide communication.
 The terminal uses full English language for all functions, eliminating
the need to remember coded commands.

17. Portable Operator’s Terminal Sample Display.

18. APOGEE Automation System Architecture