Laurel Electronics
Call (714) 434 6131 for Product Assistance
Panel Meters - Counters - Timers - Transmitters, 4-20 mA & Modbus - Ethernet - USB - RS485 - RS232

Laureate™ Quadrature Encoder Input Meter for Bidirectional Position or Rate

Accurate Position or Rate from Linear & Rotary Quadrature Encoders

Quadrature meter for linear and rotary encoders


  • Accepts differential or single-ended logic signals from quadrature encoders
  • 6-digit scalable display for position, length or rate
  • Up to 250 kpulses/sec at X1, 125 kpulses/sec at X2, 62.5 kpulses/sec at X4
  • Display update rate up to 25/s
  • Zero channel input
  • Universal 85-264 Vac / 90-300 Vdc or 10-48 Vdc / 12-32 Vac power
  • Transducer excitation output (isolated)
  • Wide choice of options:
    - 2 or 4 relays, mechanical or solid state (isolated)
    - Analog output (isolated)
    - Communications: Ethernet, WiFi, USB, RS232, RS485 (isolated)
  • -X extended temperature option from -40°C to 70°C
Quadrature meter for encoder signals

Bidirectinal Position, Length or Angle Measurement

The Laureate™ quadrature meter with the Standard counter main board accepts the A & B quadrature signals from shaft encoders or linear encoders to provide a highly accurate, scaled display of position, length, or angle in engineering units, such as ft, cm or degrees. The A & B quadrature signals are 90° out of phase, and their phase relationship determines whether up counts (+) or down counts (-) are counted. The meter totalizes the counts and then scales the total in software for display and control. A zero index signal, or Z signal, can be added as a third input to the A & B signals.

Bidrectional Rate Measurement

The Laureate™ quadrature meter with the Extended counter main board can be set up for scaled position or rate, but not for simultaneous position and rate. For example, it can display the speed of a moving slab in ft/sec. The display and control output update rate for position or rate is normally set to a maximum of 25/sec, as determined by a user-programmable gate time.

Quadrature Meter Capabilities

Quadrature Position & Rate Meter
  • One, two or four quadrature transitions may be counted at a maximum combined rate of 250 kHz and be mathematically scaled for display in engineering units from -999,999 to +999,999. Maximum pulse rates are 250 kpulses/sec at X1, 125 kpulses/sec at X2, and 62.5 kpulses/sec at X4.
  • Single-ended input signals up to 5V or balanced line driver signals up to 10V are accommodated by the quadrature signal conditioner board. Anti-jitter circuitry eliminates errors due to vibration of the encoder.
  • An excitation output from the meter can be used to power the encoder, thus avoiding the need for an external powr supply. Jumper selectable levels are 100 mA at 5V or 120 mA at 10V.
  • A zero index pulse, if available from the encoder, is interpreted by the meter as a zero reference for an integral number of revolutions of a rotary encoder, or as the home position of a linear encoder. It is used by the meter for initializing and correcting any cumulative pulse count errors. Special circuitry corrects for width of the zero index pulse.
  • In the event of a power failure, the latest total can be stored in non-volatile memory and be used as the starting point for counting when power resumes. Power fail save or zero index capabilities are alternate meter setup choices.

Unidirectional Position and Rate

If the counts are only for one direction, for example for extusions measured by an encoder wheel, only the encoder's "A" channel can be used and be output to an Extended Laureate totalizer. This model accommodates very high pulse rates up to 1 MHz, and unlike the quadrature meter, it can simultaneously track rate and total. It can also be programmed for batch control, which allows it to simultaneously track rate, batch (or current) total, and grand total or number of batches.

Additional Capabilities

Optional plug-in boards for communications and control include Ethernet, WiFi and serial communication boards, dual or quad relay boards, and an isolated analog output board. Laureates may be powered from 85-264 Vac or optionally from 12-32 Vac or 10-48 Vdc. The display is available with red or green LEDs. The 1/8 DIN case meets NEMA 4X (IP65) specifications from the front when panel mounted. Any setup functions and front panel keys can be locked out for simplified usage and security. A built-in isolated 5, 10, or 24 Vdc excitation supply can power transducers and eliminate the need for an external power supply. All power and signal connections are via UL / VDE / CSA rated screw clamp plugs.

Readout 6 LED digits, 7-segment, 14.2 mm (.56"), red or green.
Display Range -999999 to +999999, XXXXEX notation beyond 999999
Zero Adjust -999999 to +999999
Span Adjust 0 to 999999
Indicators Four LED lamps
Types Differential or single-ended quadrature
Transitions Monitored X1, X2 or X4
Max Pulse Rate 250 kpulses/sec at X1, 125 kpulses/sec X2, 62.5 kpulses/sec at X4
Position Error No error contributed by meter
Differential High Threshold +200 mV
Differential Low Threshold -200 mV
Differential Limits -11V to +14V
Single-ended High Voltage 2.5V to 10V
Single-ended Low Voltage -1V to +1V
Input Resistance, Typ. 17 kOhm
Quadrature Position Mode
Zero Adjust -999999 to +999999
Span Adjust 0 to 999999
Quadrature Rate Mode
Freq. Technique Inverse period
Conversion Time Gate time + 30 ms + 0-2 signal periods
Gate Time Selectable 10 ms to 199.99 s
Time Before Zero Out Selectable 10 ms to 199.99 s
Output & Display Update Same as conversion time
Time Base Accuracy Calibrated to ±2 ppm
Power Supply Boards (one required)
Voltage, standard 85-264 Vac or 90-300 Vdc
Voltage, optional 12-32 Vac or 10-48 Vdc
Frequency DC or 47-63 Hz
Power Consumption (typical, base meter) 1.2W @ 120 Vac, 1.5W @ 240 Vac, 1.3W @ 10 Vdc, 1.4W @ 20 Vdc, 1.55W @ 30 Vdc, 1.8W @ 40 Vdc, 2.15W @ 48 Vdc
Power Isolation 250V rms working, 2.3 kV rms per 1 min test
Excitation Output (standard)
5 Vdc 5 Vdc ± 5%, 100 mA
10 Vdc 10 Vdc ± 5%, 120 mA
24 Vdc 24 Vdc ± 5%, 50 mA
Output Isolation 50 Vdc to meter ground
Analog Output Boards (one optional)
Output levels 4-20 mA, 0-20 mA, 0-10V, -10 to +10V (single-output option)
Current compliance 2 mA at 10V ( > 5 kΩ load)
Voltage compliance 12V at 20 mA (< 600 Ω load)
Scaling Zero and full scale adjustable from -99999 to +99999
Resolution 16 bits (0.0015% of full scale)
Isolation 250V rms working, 2.3 kV rms per 1 min test
(dual analog outputs share the same ground)
Relay Output Boards (one optional)
Dual magnetic relays 2 Form C, 8A at 250 Vac or 24 Vdc, 0.3A at 250 Vdc, resistive load
Quad magnetic relays 4 Form A (NO), 8A at 250 Vac or 24 Vdc, 0.3A at 250 Vdc, resistive load
Dual solid state relays 2 Form A (NO), 120 mA at 140 Vac or 180 Vdc, resistive load
Quad solid state relays 4 Form A (NO), 120 mA at 140 Vac or 180 Vdc, resistive load
Relay commons Isolated commons for dual relays or each pair of quad relays
Relay isolation 250V rms working, 2.3 kV rms per 1 minute test
Relay latching modes Latching or non-latching
Relay active modes Active on or off, active high or low
Hysteresis modes QA passband mode, split hysteresis, span hysteresis
Communication Boards (one optional)
Board selections RS232RS485 with dual RJ11 connectors, RS485 with dual RJ45 connectors, USB, Ethernet, USB-to-RS485 gatewayEthernet-to-RS485 gateway, WiFi with built-in antenna plus USB & RS485, WiFi with external antenna plus USB & RS485
Protocols Laurel Custom ASCII (serial), Modbus RTU (serial), Modbus TCP (Ethernet or WiFi)
Digital addresses 247 (Modbus), 31 (Laurel ASCII),
Isolation 250V rms working, 2.3 kV rms per 1 min test
Operating temperature 0°C to 55°C standard, -40°C to 70°C with -X option
Storage temperature. -40°C to 85°C
Relative humidity 95% at 40°C, non-condensing
Protection NEMA-4X (IP-65) when panel mounted
Using Quadrature for Cutting to Length
Using a Laureate quadrature panel meter to cut material to length Controlling the repetitive cutting of material to length is an excellent application of the Laureate quadrature meter. The quadrature encoder shares the shaft of a sensing wheel, whose rotation corresponds to lineal displacement of material. The meter compares the displacement reading against setpoint information, and then uses its dual relays to first slow down and then cut the material.
Using Quadrature for X-Y Positioning
Using a Laureate quadrature panel meter for X-Y positioning Accurate X-Y position or rate can be obtained from two shaft encoders, which convert linear position to quadrature signals as a shaft turns. In addition to serving as a display, each Laureate can use its optional dual relay setpoint capability for closed loop control. It can also transmit data via RS232, RS485, or a 4-20 mA analog signal.
Using Quadrature to Monitor a Drilling Operation
Using a Laureate quadrature meter to monitor an oil drilling operation Quadrature can be used to track position and vertical drilling speed of the bit in an oil drilling operation. A shaft encoder is rotated by a cable that moves with the drilling shaft. In this application, the same encoder signal is applied to a Laureate quadrature meter for position, and to a second quadrature meter for rate. Both meters can be scaled to read out in appropriate engineering units, such as feet and inches per minute, and can be alarmed. A Laureate 6-digit remote display could be added to read out peak rate.
For applications assistance, phone 714-434-6131 ext. 104, or email
Ordering Guide
Laureate™ Quadrature Position & Rate Meters
Click on the radio buttons to build a model number with pricing as shown below. Prices are in US dollars and do not include shipping or duty charges (export sales). Please see our explanations and limitations applicable to pricing and online orders. Prices shown are in US Dollars and are Laurel's manufacturer's suggested retail price (MSRP) in the USA. Orders are processed manually, not directly by our shopping cart system. You don't have to supply credit card information when placing an online order.

North American Orders. Laurel does not sell factory-direct in the USA or Canada. Online sales orders are filled through distribution. During the ordering process, you will have the chance to select an authorized Laurel distributor, or you can ask Laurel to refer you to a distributor. The distributor will then contact you to quote shipping, tax and duty (where applicable), and arrange for payment.

International Orders. If your ship-to address indicates that you are outside of the USA or Canada and Laurel has a distributor in your country, we will forward your order to that distributor for follow-up. If Laurel does not have a distributor in your country, we will email you an order acknowledgment and a pro forma invoice which states the product price, shipping charges, and wire transfer information, which includes a $25 bank wire transfer fee.

Questions about your order? Please email your distributor or
Main Board L   Laureate Series multifunction counter / timer / rate meter main board $169
Display Color 5   Basic meter, green LEDs $0
6   Basic meter, red LEDs $0
7   Extended meter, green LEDs $41
8   Extended meter, red LEDs $41
Power 0  Isolated 85-264 Vac or 90-300 Vdc $75
1  Isolated 12-32 Vac or 10-48 Vdc $115
0  None $0
1  Two 8A Form C contact relays $101
2  Two 120 mA solid state relays $70
3  Four 8A Form A contact relays $128
4  Four 120 mA solid state relays $96
0  None $0
1  Single Isolated 4-20 mA, 0-20 mA, 0-10 V, -10 to +10V $115
2  Dual isolated 4-20 mA, 0-20 mA, 0-10V $172
0  None $0
1  RS232 (L232) $81
2  RS485 (L485, dual RJ11 connectors) $109
4  RS485 (LMOD, dual RJ45 connectors, not for new design) $135
5  USB (LUSB) $81
6  USB-to-RS485 gateway (LUSB485) $135
7  Ethernet (LNET) $237
8  Ethernet-to-RS485 gateway (LNET485) $259
A  Ethernet + USB (LNET1) $182
B  Ethernet + RS485 (LNET1485) $204
C  WiFi + USB internal antenna (LWIFI) $171
D  WiFi + USB, external antenna (LWIFIX) $193
E  WiFi + USB + RS485, internal antenna (LWIFI485) $204
F  WiFi + USB + RS485, external antenna (LWIFIX485) $226
QD  Quadrature $123
CBL01  RS232 cable, RJ11 to DB9, 7 ft. Connects RS232 ports of meter and PC. $23
CBL02  USB to RS232 adapter cable. Combination of CBL02 and CBL01 connects meter RS232 port to PC USB port. Combination of CBL02 and CBL04 connects transmitter RS232 terminals to PC USB port. $47
CBL03-1  6-wire data cable, RJ11 to RJ11, 1 ft. Used to daisy chain meters via RS485. $10
CBL03-7  6-wire data cable, RJ11 to RJ11, 7 ft. Used to daisy chain meters via RS485. $10
CBL05  USB cable, A-B. Connects USB ports of meter and PC. $19
CBL06  USB to RS485 adapter cable, half duplex, RJ11 to USB. Connects meter RS485 port to PC USB port. $47
CASE1  Benchtop Laboratory Case for One 1/8 DIN Meter $140
CASE2  Benchtop Laboratory Case for Two 1/8 DIN Meters $140
NL  Meter Lens with Button Pads but no Laurels Logo $5
BL  Meter Lens without Button Pads or Laurels Logo $5
IPC  Splash-proof Cover $48
BOX1  NEMA-4 Enclosure $169
BOX2  NEMA-4 Enclosure plus IPC $218
Configured model number L50000QD
Configured price per model $367
Quantity 1
Extended price $367
Legal Information
facebook   G+   twitter   linkedin
© 1990-2024 Laurel Electronics