Table 10 – LEDs

The LEDs on the RTU Open Control Board (see Fig. 57) show the status of certain functions:

If this LED is on...

 

Status is...

 

 

 

Power

 

RTU Open has power

 

 

 

Rx

 

RTU Open is receiving data from the network segment

 

 

 

Tx

 

RTU Open is transmitting data over the network segment

 

 

 

DO#

 

The digital output is active

 

The Run and Error LEDs indicate control module and network status

If Run LED shows...

And Error LED shows...

2 flashes per second

Off

 

 

2 flashes per second

2 flashes,

alternating with Run LED

 

2 flashes per second

3 flashes,

then off

 

2 flashes per second

4 flashes,

then pause

 

 

 

2 flashes per second

On

 

 

5 flashes per second

On

 

 

5 flashes per second

Off

 

 

7 flashes per second

7 flashes per second, alternating with

Run LED

 

 

 

14 flashes per second

14 flashes per second,

alternating with Run LED

 

On

On

 

 

Status is...

Normal

Five minute auto---restart delay after system error

Control module has just been formatted

Two or more devices on this network have the same ARC156 network address

Exec halted after frequent system errors or control programs halted

Exec start---up aborted, Boot is running Firmware transfer in progress, Boot is running

Ten second recovery period after brownout

Brownout

Failure. Try the following solutions:

STurn RTU Open off, then on. S Format RTU Open.

S Download memory to RTU Open. S Replace RTU Open.

48HC

NOTE: Refer to Catalog No. 48-50HCTQ-01T for complete configuration of RTU Open, operating sequences and troubleshooting information. Refer to RTU Open Controller Integration Guide (Catalog No. 11-808-428-01) for details on configuration and troubleshooting of connected networks. Have a copy of these manuals available at unit start-up.

Outdoor Air Enthalpy Control

Enthalpy

 

Switch

 

24V

RED

GND

BLK

LOW

GRA

PL6-1 (24-V)

PL6-4 (COM)

7CTB ECON (P’LINK: to J4-2) or (RTU Open: to J2-6)

(PNO 33CSENTHSW)

The enthalpy control (33CSENTHSW) is available as a field-installed accessory to be used with the EconoMi$er2 damper system. The outdoor air enthalpy sensor is part of the enthalpy control. (The separate field-installed accessory return air enthalpy sensor (33CSENTSEN) is required for differential enthalpy control. See Fig. 71.)

Locate the enthalpy control in the economizer next to the Actuator Motor. Locate two GRA leads in the factory harness and connect the gray lead labeled “ESL” to the terminal labeled “LOW”. See Fig. 71. Connect the enthalpy control power input terminals to economizer actuator power leads RED (connect to 24V) and BLK (connect to GND).

Factory Wiring Harness

C11160

Fig. 71 - Enthalpy Switch (33CSENTHSW) Connections

The outdoor enthalpy changeover setpoint is set at the enthalpy controller.

Differential Enthalpy Control —

Differential enthalpy control is provided by sensing and comparing the outside air and return air enthalpy conditions. Install the outdoor air enthalpy control as described above. Add and install a return air enthalpy sensor (see Fig. 72).

45

Page 45
Image 45
Carrier 48HC installation instructions Outdoor Air Enthalpy Control, LEDs, Differential Enthalpy Control

48HC specifications

The Carrier 48HC is a highly efficient rooftop HVAC unit designed for commercial applications that prioritize both performance and energy savings. This unit embodies Carrier's commitment to innovation by integrating advanced technologies and features that address the modern demands of building climate control.

One of the standout features of the Carrier 48HC is its exceptional energy efficiency. Employing the latest in variable-speed compressor technology, the unit adjusts its output based on the specific cooling needs of the space, which not only enhances comfort levels but also significantly reduces energy consumption. This feature is crucial for businesses looking to lower their operational costs while minimizing their environmental impact.

The Carrier 48HC is also equipped with a comprehensive range of control options. Through its intelligent control systems, users can utilize features such as demand ventilation, which optimizes indoor air quality while maintaining energy efficiency. The integration with building management systems (BMS) further enhances operational effectiveness, allowing real-time monitoring and adjustments from a centralized point.

Additionally, the 48HC is designed with durability in mind. Its robust construction resists harsh weather conditions and ensures long-lasting performance. The unit features advanced corrosion-resistant materials and coatings, which prolong its lifespan and reduce maintenance needs. This durability makes the 48HC a reliable choice for varying environments, whether it’s an industrial setting or a more delicate commercial space.

The unit’s compact design also deserves mention, as it facilitates easier installation on rooftops without taking up excessive space. The modular design allows for customization, enabling businesses to tailor their systems to fit specific heating and cooling requirements.

In terms of comfort, the Carrier 48HC employs efficient air distribution technology that ensures even airflow throughout the space. This greatly enhances occupant comfort by eliminating hot or cold spots, promoting a consistent indoor climate.

Finally, the 48HC complies with stringent environmental regulations and standards. With options for environmentally-friendly refrigerants, it supports businesses in their sustainability efforts while operating effectively under current regulations.

In summary, the Carrier 48HC stands out in the crowded HVAC market due to its advanced technology, energy efficiency, durability, and adaptability for commercial applications, making it a top choice for those looking to invest in a reliable and effective climate control solution.