ED312 Ethernet Time Display
Now available with Power over Ethernet (PoE)
- Theory of Operation
- Network Interface
- Power over Ethernet (PoE)
- Serial Port
- Relay Output
- Power Supply
- Software Interface
- Physical Specifications
is a six-digit, high visibility (4" high digits), time of day Ethernet
wall clock. The ED312's Ethernet connection allows its internal
time-of-day clock to be periodically synchronized with a host computer
clock over the network. (See the ED210
for a four-digit model.)
Time can be displayed in either standard military (00:00 - 23:59) format or in AM/PM (12:00AM - 11:59PM) format. Alarms can be set to trigger either the internal bell or an optional relay. The network interface supports both 10BaseT and 100BaseT Ethernet connections.
wireless connectivity is also available.
Some of the uses for the ED312:
- SNTP wall clock
- SNTP time display
- SNTP digital time display
- TCP/IP wall clock
- TCP/IP time display
- TCP/IP digital time display
- Ethernet wall clock
- Ethernet time display
- Ethernet digital time display
The ED312 can be used to display the current time, the timer
value, or a message string. Selection of the display mode is dynamic
and can be controlled through the network interface. A standard
Telnet client or special application program can be used to control
& configure the time display device.
As an employee time display, it can be synchronized to a master
system clock via the network. Normally, a host computer on the
network is designated as the master clock and will periodically
update the time and date on all of the employee time clock (EC305)
devices. The ED312 time display can be updated at the same time
creating a completely synchronized timing system. A utility program
(ET200UP) is provided with the ED312 that can be used to perform
the update. If the host computer has internet access the system
clock can also be synchronized with the NIST atomic clock.
The ED312 can be programmed to trigger an alarm at a certain time of day. Up to 32 alarms can be set and each alarm will either activate the internal bell or one of the 4 optional relay outputs. Alarms that trigger a relay output can be used to activate exter-nal bells, lights, counters, etc. The length of time that a relay is active can also be set by the alarm.
The ED312 connects to a 10BaseT or 100BaseT hub (or switch) via a standard RJ-45 Ethernet (CAT 5) cable. From a network perspective it occupies a single "socket" at a specified TCP/IP address and port number. The device must be configured with a unique IP address, net mask, and port number BEFORE it is installed on the network (see "Net-work Configuration"). The host software communi-cates with the ED210 by establishing a connection with it and then sending and receiving ASCII text command strings (see Software Interface
Power over Ethernet (PoE) capacity is now available.
The ED312 has a six (6) digit, seven (7) segment LED display which displays the time in HH:MM format. Each of the red digits is 4" high and can be viewed from a distance of 100 feet. In the upper left corner is a dot use as a PM indicator used when the time is displayed in the Am/Pm mode. When ED312 is first powered on all display segments will be lit for about 2 seconds to verify their operation.
The serial RS-232 port is used to initially configure the ED312 via the "Aux Command Mode" which provides local communications with a terminal or computer. Access to the serial port is provided by a DB9M connector configured as a DTE device.
The ED312 can be equipped with four (4) solid state relay (SSR) outputs that can be individually activated as an alarm output. Each relay has a single "form A" contact rated at 10va (100vdc, 100ma.) maximum. If larger loads must be controlled use of an external relay is required. The relay outputs can be optionally configured to directly activate an external 12Vdc relay. For more information on external connections see application note AN0202
The ED312 is powered by a 12Vdc power adapter that plugs directly into a 120vac receptacle. Typical power consumption is less than 12 watts. Alternate power supplies are available for international customers or the ED312 can be powered using a 12Vdc supply connected to the power jack.
The ED312 includes a bracket on the back side which allows the time display to be mounted on a vertical surface. Two (2) key hole slots in the bracket can be used to hang the ED312 with screws on a vertical surface. The bracket can be inverted or removed as desired.
Software communications with the ED312 is simple and straight forward. The primary TCP/IP port is used for communications with the user application program. Normally, the host software (client) is responsible for establishing a network connection with the ED312 (server) on a specified port. Alternately, the ED312 can be configured to automatically establish a connec-tion (client) with a host computer application (server) using the SERVER parameter.
Once the connection is established the host applica-tion software can set the time & date or other com-mands to the ED312. Typically, the data transfer is accomplished in ASCII character strings to minimize network packet traffic. The communications protocol is determined by the emulation mode and can be changed dynamically by the host software.
- Large 4", 7 segment
- 10/100BaseT Ethernet (RJ-45)
- Serial Port
- Input/Output (RS-232)
- Optional Relay control outputs (2 or 4)
- 23.5"W x 6.9"H x 3.3"D
- 6.8 Lbs.
- Power Consumption -
- Standard Unit: 15 Watts (max)
- Temperature Ranges:
- Operating: 0ºC to 60ºC (32ºF to 140ºF)
- Storage Temperature: -30ºC to 70ºC (-20ºF to 158ºF)