LCD
The liquid crystal display (LCD) is used to display meter data and status information. Figure 3-1 shows the dimensions of the LCD.
Figure 3-1. LCD dimensions
As shown in Figure 3-2, the LCD is divided into different display regions.
Figure 3-2. LCD regions P - +P Q Q + - 7
Approximate dimensions in millimeters 9.5 27 32 77 85 5 2 3.5 1.4 Viewing area P - +P Q Q + -
L L L
1 2 3 COM 0 1 2 Error/warning indicator Energy direction indicator Display quantity Tariff indicators 1 to 8 (left to right) EOI indicatorLC indicator Cover removed indicator Test mode indicator Power/energy units identifier Comm. port indicator
Alternate mode indicator Quantity identifier Low battery indicator
Phase indicators (3) Tec hn ica l m anu al
All A1800 ALPHA meters have a backlight option for the LCD. The LCD can be illuminated by pressing one of the push buttons, making it easier to read the LCD in no-light or low-light conditions. The backlight option must be specified at the time of ordering. See “Using the backlight” on page 3-6 for more information.
Quantity identifier. This 7-digit region identifies the displayed quantity as defined and programmed with Elster meter support software. An identifier can be assigned to most display quantities in the display sequence. See Appendix B, “Display table,” for more information.
Display quantity. This 8-digit display on the LCD shows either metered quantities or other displayable information, depending upon how the A1800 ALPHA meter has been
programmed.
The displayable digits are definable using Elster meter support software for both energy and demand readings. From 3 to 8 digits with up to 4 decimal places can be used. These digits are also used to report error codes for the following error conditions:
• operational errors (E1, E2, or E3)
• system instrumentation and service test errors (SE) • warnings (W1 or W2)
• communication codes (COM 0, COM 1, COM 2)
For instrumentation values and tests, numeric values may be replaced by or mixed with alphabetic characters to better define the value. See Appendix B, “Display table,” for more information.
Phase indicators. Each phase indicator (L1, L2, and L3) corresponds to a line voltage (Line 1, Line 2, and Line 3, respectively) present on the A1800 ALPHA meter connections. The state of the indicators correspond to the following:
• If the indicators are on, then all expected line voltages are present.
• If an indicator is blinking, then that expected line voltage is either missing or below the defined threshold for voltage sag detection.
• If an indicator is off, the line is not expected for the configured meter type. See “Voltage sags”for more details on momentary voltage sag detection and the phase indicators.
Energy direction indicators. The energy direction indicators display the quadrant and direction of the last Wh (active) and varh (reactive) energy flow. Positive energy flow is energy delivered to the consumer load, while reverse energy flow is energy received from the consumer load. Figure 3-3 shows the meaning of each energy direction indicator.
The energy direction indicators turn on to display energy flow direction when any of the meter phases are measuring energy flow (that is, when one of the line currents is above the meter starting threshold).
Figure 3-3. Energy direction indicators
Positive reactive energy
Reverse reactive energy Positive active energy Reverse active energy
On meters with the Always Positive option, the +P indicator is on continuously whenever kWh flow of any direction is detected. The –P indicator is inoperative for this meter configuration (see “Always Positive” on page 2-13 for more information).
Power/energy units identifier. The power/energy units identifier is used to indicate the unit of measurement for the quantity displayed on the meter’s LCD. In some cases, it may not be possible to represent the displayed quantity using the power/energy units identifier. If this is the case, then the power/energy units identifier will not be used. Instead, the quantity will be identified either using the quantity identifier or appending the unit to the display quantity.
Alternate display indicator. This indicator (*) displays when the A1800 ALPHA meter is operating in alternate mode. This indicator also displays during the all segment test of the LCD.
See “Operating modes” on page 3-7 for more information on the different operating modes.
Error indicator. The error indicator flashes when any error condition is present or remains on if a warning condition is present. When the error indicator is on, the LCD will also display the appropriate error or warning code. See “System service error codes” on page 4-10 and “Codes and warnings” on page 6-2 for details.
Note: This indicator also turns on during the LCD all-segments test.
Low battery indicator. The low battery indicator is turned on when the TOU battery voltage is low or when the TOU battery is missing. Additionally, the low battery warning display item (if included in the display list) also is displayed.
Note: This indicator also turns on during the LCD all-segments test.
Active COM port indicator. The active COM port indicator indicates that a communication session is in progress and which COM port is being used.
See “Communication codes” on page 6-8 for additional details.
Display indicators. The 12 display indicators () are used to more precisely identify the information displayed on the meter’s LCD.
Note: These identifiers may be shown individually or in combination to describe a particular displayed quantity.
Note: The manufacturer’s nameplate details the meaning of the display indicators. See Appendix C, “Nameplate and style number information.”
Tariff indicators. The tariff indicators (T1, T2, T3, and T4) indicate the current tariff. If the displayed quantity is a TOU item (for example, tariff 1 total kWh), the corresponding indicator (T1) turns on. If the quantity’s tariff is active at the time, the tariff indicator flashes.
Note: The active tariff indicators also turns on during the LCD all-segments test.
EOI indicator. The end-of-interval (EOI) indicator is used to verify the timing of the demand interval. Ten seconds before the end of the demand interval, the EOI indicator will be turned on and remain on until the end of the interval.
Table 3-1. Port codes
Code Port
COM 0 Optical port COM 1 Remote port 1 COM 2 Remote port 2
For rolling demand, the EOI indicator turns on for 10 seconds before the end of each subinterval.
Transformer and line loss compensation indicator. The loss compensation (LC) indicator indicates the meter is currently compensating for transformer and line loss.
Cover tamper indicator. The cover tamper (TC) indicator indicates that either the terminal cover or the meter cover is removed. This may indicate that tampering has occurred on the meter. The TC indicator turns off when all the covers are in place. See “Cover tamper detection switches” on page 2-5 for additional information.
Test mode indicator. The test (TST) mode indicator indicates that the meter is currently operating in test mode. See “Test mode” on page 3-8 for details.