An AS-B server is a powerful automation server that features both onboard I/O and built-in power supply. Like the other automation servers, the AS-B server is a Schneider Electric manufactured embedded device that generally serves as the lowest tier EcoStruxure BMS server within the EcoStruxure BMS. The automation server controls and supervises equipment, typically HVAC equipment. The AS-B server uses its onboard I/O with connected field devices, such as sensors and actuators, to do that.
The AS-B server is installed on DIN rails in cabinets.
The AS-B server comes in eight models that offer two different sets of I/O point count and I/O mix.
Model |
I/O Points |
AS-B-24 |
24 |
AS-B-24H |
24 |
AS-B-24-P |
24 |
AS-B-24H-P |
24 |
AS-B-36 |
36 |
AS-B-36H |
36 |
AS-B-36-P |
36 |
AS-B-36H-P |
36 |
AS-B servers with “H” in the product name are equipped with a display for output override.
AS-B servers with “P” in the product name are hardware only. An AS-B software package needs to be purchased separately. For more information, see the AS-B Specification Sheet.
AS-B servers with 36 I/O points have the same small footprint as AS-B servers with 24 I/O points.
The AS-B server offers a mix of I/O point types that match a wide variety of HVAC applications. Most of the I/O points are universal inputs/outputs, which are highly flexible and can be configured as either inputs or outputs.
For more information, see AS-B Server Onboard I/O .
The output override function allows you to manually override outputs. This function can be used for testing, commissioning, and maintenance of equipment.
For more information, see Output Override Function .
The device has a built-in power supply designed to accommodate 24 VAC or 24 VDC input power. The main AC/DC input (L/+ and N/-) is galvanically isolated from the electronics. This removes the risk of damage due to earth currents and permits the input power to be wired without concern for AC polarity matching.
An AS-B server has two types of memory:
256 MB DDR2 SDRAM (for program execution)
4 GB eMMC memory (for storage)
If a power outage occurs, all important variables are automatically saved to the eMMC memory before complete shutdown. When power returns, this data retention function helps ensure that AS-B can continue to run with the correct set of values.
The AS-B server natively communicates with two of the most popular communication protocols:
BACnet: The AS-B server directly communicates to BACnet/IP and BACnet MS/TP networks, which provides access to MP and RP controllers, b3 BACnet devices, and BACnet devices. The AS-B server also supports BACnet/SC applications as a BACnet/SC node or BACnet/SC router, which allows the AS-B server to be in BACnet/SC networks and support applications that connect BACnet/IP or MS/TP networks with BACnet/SC networks.
Modbus: The AS-B server natively integrates Modbus RS-485 client and server configurations, as well as IP client and server. This integration provides access to devices that communicate on the Modbus protocol, such as power meters, circuit breakers, and lighting controllers.
AS-B has the following communication ports:
2 Ethernet 10/100 megabit ports
1 RS-485 port
1 USB host port
1 USB device port
For more information, see AS-B Server Communication Ports .
AS-B servers use pluggable terminal blocks, which are easy to install and remove from the device. The terminal blocks are delivered with the device.
For more information, see AS-B Server Screw Terminals .
There are five LEDs on the front panel of the AS-B server.
For more information, see AS-B Server LEDs .
There are four different types of reset for the automation servers: warm start, cold start, reset, and reset to DFU mode. Depending on the type of reset, the automation server can be reset using the reset button or a command from WorkStation.
For more information, see Automation Server Reset Functions .
The AS-B servers are designed for installation on DIN rails in a cabinet.
For more information, see AS-B Server Device Installation .
The wiring recommendations provide guidance regarding wiring of the Central IO modules, automation servers, BACnet/IP devices, RP controller expansion modules, and Operator Display.
For more information, see Wiring .
Before you engineer an AS-B server, install the AS-B server software on the server using Device Administrator. The software is not pre-loaded on the AS-B servers.
For more information, see Installing AS-P or AS-B Software .
Backup and Restore helps assure that automation server data can be restored to a replacement automation server in the event of detected failure, or to the same automation server in the event of data loss. As a precaution, you back up your automation servers regularly so that you can use the most current backup to restore the automation server data to a replacement automation server. You also configure the new automation server to match the name and the network settings of the replaced automation server so the system can identify this automation server when online.
For more information, see Automation Server Replacement Using Restore .
AC input | |
Nominal voltage
|
24 VAC
|
Operating voltage range
|
+/- 20 %
|
Frequency
|
50/60 Hz
|
Maximum current
|
0.5 A rms
|
Recommended transformer rating
|
≥15 VA
|
DC input | |
Nominal voltage
|
24 to 30 VDC
|
Operating voltage range
|
21 to 33 VDC
|
Maximum power consumption
|
10 W
|
Environment | |
Ambient temperature, operating
|
0 to 50 °C (32 to 122 °F)
|
Ambient temperature, storage
|
-20 to +70 °C (-4 to +158 °F)
|
Maximum humidity
|
95 % RH non-condensing
|
Material | |
Plastic flame rating
|
UL94-5VB
|
Enclosure
|
PC/ABS
|
Ingress protection rating
|
IP 20
|
Mechanical | |
Dimensions
|
198 W x 110 H x 64 D mm (7.8 W x 4.3 H x 2.5 D in.)
|
|
|
Weight, including terminal blocks
|
0.504 kg (1.111 lb)
a
|
a) The weight includes the display and keys, which are 0.022 kg (0.049 lb). | |
Weight, excluding terminal blocks
|
0.420 kg (0.926 lb)
a
|
a) The weight includes the display and keys, which are 0.022 kg (0.049 lb). | |
Real-time clock | |
Accuracy in runtime mode
|
NTP server
|
Accuracy in backup mode, at 25 °C (77 °F)
|
+/-52 seconds per month
|
Backup time, at 25 °C (77 °F)
|
10 days
|
Communication ports | |
Ethernet
|
Dual 10/100BASE-TX (RJ45)
|
USB
|
1 USB 2.0 device port (mini-B)
|
1 USB 2.0 host port (type-A), 5 VDC, 2.5 W
|
|
RS-485
|
2-wire port, bias 5.0 VDC
|
Communications | |
BACnet
|
BACnet/IP and MS/TP, port configurable, default 47808
|
BACnet/SC, port configurable, no default port
|
|
BTL B-BC (BACnet Building Controller)
a
|
|
a) See the BTL Product Catalog for up-to-date details on BTL listed firmware revisions on BACnet International's home page. | |
Modbus
|
Modbus TCP, client and server
|
Serial, RS-485, client and server
|
|
TCP
|
Binary, port fixed, 4444
|
HTTP
|
Non-binary, port configurable, default 80
|
HTTPS
|
Encrypted supporting TLS 1.3, 1.2, 1.1
a
, and 1.0
a
, port configurable default 443
|
a) Disabled by default. | |
SMTP
|
Email sending, port configurable, default 25
|
SMTPS
|
Email sending, port configurable, default 587
|
SNMP
|
version 3
|
Network supervision using poll and trap
|
|
Application alarm distribution using trap
|
|
CPU | |
Frequency
|
333 MHz
|
Type
|
SPEAr320S, ARM926 core
|
DDR2 SDRAM
|
256 MB
|
eMMC memory
|
4 GB
|
Memory backup
|
Yes, battery-free, no maintenance
|
The AS-B servers internal configuration with regards to the signal ground is shown in the following figure.
The earth ground terminal (