NÅNO Flow Computer

Rugged & Reliable, Repeatable & Predicable

Designed for both control rooms and field mounting (-40 °C to +85 °C)

Low Power for a cool and reliable long service life

MID approvals from NMi & NMRO

Compact size simplifies refits and reduces cost of new installations

3D Model

Field I/O

Digital Status Inputs – 9 off

Individually opto-isolated inputs
Maximum input voltage = 32 V
Minimum input on voltage = 10 V
Maximum input off voltage = 3 V
Input impedance 2 kΩ typical
Protection surge and reverse voltage protection
Fleeting input detection

Digital Status Outputs – 8 off

Individually optically isolated
Maximum output current = 100 mA
Maximum output saturation voltage = 2.1 V @ 100 mA
Maximum output standoff voltage = 32 V, limited by input protection
When powered off or reset, all digital outputs are OFF
Two outputs can be used as pulse outputs or PWM outputs
Frequency range is DC to 500 Hz
PWM mode 0% to 100% in 0.2% steps

Meter Pulse Inputs & Period Measurement – 4 off

Inputs can use differential or single ended inputs
Inputs are individually opto-coupled
Input signal levels from ±3.5 V to ±24 V
Input current minimum = 2.5 mA
Input impedance = 1 kΩ
Frequency range from DC to 10 kHz
Inputs A & B feature back-to-back optos, allowing full quiescent line and electronic integrity testing, when used with differential pre‑amps such as the ST106
Dual Pulse compliant inputs A & B support IP 252/76, ISO6551 or API Ch 5.5 level A or B, with line integrity, even when static
Accuracy of period measurement = 2.5 ppm
Period resolution = 5 ns

Raw Pulse Bus

Digital ground referenced differential transceiver
Enable & direction software controlled
Used to bus together multiple streams to a common prover
RS422 compatible drive & receive levels
Maximum output frequency 10 kHz

Alarm Relay

The relay used for the Gen3 hardware is a PhotoMOS solid state change-over relay
Both Form A (Normally Open) & Form B (Normally Closed) outputs provided
Maximum current 1 A (de-rated to 0.5 A for operation above 75 °C ambient)
Maximum voltage 32 V, limited by input protection
Isolation = 100 V
Released on de-power, watchdog restart or software command

Analogue Inputs – 6 off

Type of inputs: 1 to 5 Volt or 4-20 mA, differential inputs
All channels individually isolated to 50 V RMS in voltage and current input mode
Conversion Method: 24 bit Sigma-Delta ADC
Effective resolution: More than 18 bits, auto zero, auto calibrate
Conversion time: Less than 100 ms per channel
All channels can be acquired simultaneously
Series mode rejection: >100 dB at 50 Hz and 60 Hz
Voltage common mode range: ±50 V relative to computer ground or other input

RTD Inputs – 2 off

4 wire Kelvin connection using Pt100 RTD
Temperature measuring range: -100 °C to +300 °C
Resolution: 0.01 °C
Accuracy: ±0.05 °C, -100 °C to +200 °C and ±0.1 °C, +200 °C to +300 °C
PRT cables loop resistance up to 600 Ω
Continuous cable integrity tests for excitation current and voltages allow open and short circuit detection
RTD current sources 1 mA nominal
3 wire mode not supported
Each RTD uses one analog input channel

Analogue Outputs – 2 off

Each channel is individually isolated
Current controlled 0 to 24 mA
Can be used to sink or source power
Resolution: 14 bits
Accuracy: ±0.1% at 23 °C
Temperature Coefficient: 10 ppm / °C
Minimum load loop resistance: Safe down to 0 Ω from +32 V external supply
Maximum load loop resistance: 1 kΩ when powered from +24 V external
Maximum external supply: 32 V
Output form: Isolated active current controller
Number of field connections: 2 terminals per channel
Update time: 500 ms to within 1%

Hardware Overview

Mechanical

Length on Rail: 188mm
Height: 56mm
Width across Rail: 134mm
Weight: 650 grams
Structure: PVC extrusion with stainless steel lid
Mounting: 35mm symmetrical Top Hat rail to EN50022 and asymmetric G-type rail to EN50035

Environmental

-40°C to +85°C operating temperature range
-25°C to +55°C for MID certified installations
-60°C to +100°C storage (without integral display)
Humidity: Up to 95% non-condensing
Safety classification: For use in a safe area
High vibration tolerance due to robust mechanical design

Input Power

Input Voltage & Current: 11.5V to 30V DC, 4.5W nominal, 6W max
Suitable for 12V Solar powered systems
Digital only version is typically 3 Watts
DC Inputs: 2 off, allowing direct connection to redundant supplies
Galvanic isolation: Minimum of 50V RMS to Instrument Ground
Input Ripple: Maximum 2V peak to peak
Input protection: Non-replaceable 1A input fuse

Clock

Accuracy Powered-Off
- Capacitor supported calendar better than 10 Seconds per day
- Ensures logs and reports are in sequential time/date order following a power interruption
- NOTE: Capacitor only supports up to 2 days powered off before clock is reset to last know power-off time
Accuracy Powered-On
- 0.5 Seconds per day over full temperature range

Processor & Memory

CPU: 800 MHz ARM Cortex-A8 highly integrated SoC processor system
Memory
- SRAM: Not required, by design, no batteries needed.
- FRAM: 128 KBytes or 512 KBytes
- NOR: Flash 128 MBytes
- DRAM: 256 MBytes, DDR3 with 400MHz bus interface
Silicon Serial No: Globally unique 48 bit address and 2 Kbit EEPROM, 200 year retention

Communications

Four Serial ports
- 1 x RS232
  Signals: TX, RX, RTS, CTS, GND
- 1 x RS485 (2-wire), galvanically isolated
  Signals: A, B, Screen
- 2 x RS422/RS485 (2-wire and 4-wire)
  Signals: TX+, TX-, RX+, RX-, Screen
Two Ethernet ports supporting 10/100MHz half & full duplex

Software Overview

Approvals

MID certified by both NMi and NMRO
OIML R117 Certified
EMC Directive 2014/30/EU
EU 2015/863 RoHS-3 directive
ISO9001 and AS9100 approved electronics manufacturers
Conflict Minerals compliant with RMI2020 and EU ‘Conflict Minerals’ Regulation (2017/821)

General

State-machine architecture based on a 500 ms application cycle time
Report storage
- 6 zones, each with 1500 report slots
- 10 zones, each with 250 report slots
Flexible report routing to send reports to printer(s), FTP and/or SD card
Alarm log storage
- Set, Clear & Accept logged separately
- 1500 log entries
Event log storage
- System (1500 log entries)
- Operator (2500 log entries)
- Metrology (1500 log entries)
- Security (1500 log entries)
- Application (1500 log entries)
ALV (Additional Log Values)
- Each Alarm or Event entry can also contain a snapshot of up-to 13 data-points
- Useful for diagnostics, debugging or forensic analysis
Data Logging facility (aka “Historicals”)
- Each data record supports up to 13 data-points
- 3 “non-volatile” storage zones with 20,000 record slots
- 1 further “volatile” zone with 86,400 record slots allowing logging every ½ second for 24 hours
- Data can be downloaded as a TSV file
Support for three printers:
- Printer #1 : Serial (CP437) or Networked
- Printer #2 : Networked only
- Printer #3 : Networked only

Integrated Web Server

View and download Reports, Alarms & Events using Calendar View
- Download Reports as Text or PDF
- Download Alarms & Events as TSV
View and download “historicals” data
Configure Date & Time manually or via NTP
Support for Time Zones
Support for Daylight Saving Time
Local Panel mimic for remote support
Browse contents of local SD card
Configure Printer settings
Configure Network settings