Neptune 800 Series Mechanical Register

The 800 series register is the latest of four multi-function devices specifically designed for petroleum distribution and industrial process industries. Some models allow automatic preset deliveries via mechanical valve and Weights and Measures approved ticket printing.


The 800 Series Registers consist of the Model 830 Series and the Model 840 Series. Model 830 Series registers are in tenths and the Model 840 Series registers are in units.

Models 831 and 841 are direct reading resettable registers with the basic non-resettable totalizer.

Models 832 and 842 are the basic 830 and 840 features plus a preset register that provides automatic deliveries. The operator sets the register for the desired quantity from the front panel. The flow will cut off automatically at the exact volume desired when used in conjunction with either a mechanical valve or a solenoid actuated valve. There are two preset models available, a single trip for one stage shutoff or a double trip for two stage shutoff (delivery decreases, then the final shutoff stops the delivery).

Models 833 and 843 are the basic 830 and 840 features plus a printer register that prints a receipt or ticket showing the readings before and after delivery. The register locks the ticket during delivery to prevent fraud. Providing two letter wheels in the register makes it possible to print a letter code on the ticket to identify the flowmeter or truck. These letter wheels can print any single letter or combination of two letters from A to J, omitting I. Additionally, three serial number wheels are provided in the register to number each ticket consecutively from 000 to 999. There are four printer models available:

  • Accumulative Face Up (most commonly used): Prints beginning reading and the final reading
  • Accumulative Face Down (for outside use): Prints beginning reading and the final reading
  • Zero Start Face Up (for larger deliveries): Prints all zeros and the actual delivery
  • Zero Start Face Down (for larger deliveries): Prints all zeros and the actual delivery

Models 834 and 844 are printer-preset registers that combine the features of the other registers. They contain the preset quantity control plus the printed ticket features.


  • Standard eight digit non-resettable totalizer, five digit delivery display, four preset and five or six digit printer
  • Measurement in Gallons, tenths of gallons, litres, dekalitres, pounds and kilograms
  • High visibility ¾” wheels
  • Long life, precision die cast Zamac printer wheels provide clear, sharp, easy to read tickets


Tech Sheet
O&M Manual
Parts List

Neptune E4000 Electronic Register

The Neptune E4000 electronic register automates transaction operations for deliveries of LPG, distillate fuels, and other commercially distributed liquids through flow meters on bulk delivery trucks. Designed for compatibility with emerging automation technologies, the E4000 offers the ability to modernize truck metering operations today and provides a platform for data collection technology tomorrow. Its improved accuracy and efficiency mean less loss, providing a fast return on investment and safeguarding future profits.

Smarter Today

  • Easy to use, menu driven display
  • Start with simple pump and print (imitate your mechanical register)
  • Electronic temperature compensation (accurate, rapid response)
  • Stand-alone pricing (print invoices directly from the truck)
  • Ten products, ten prices
  • Configure register from laptop computer

Smarter Tomorrow

  • Add data collection devices (hand held, laptop, wireless) without the need for additional register hardware.
  • No requirement for early commitment to proprietary technology.
  • Interface with popular industry office software packages.

However you manage transactions, Neptune value will help you do more today…and much more tomorrow.


Installation Manual →
Tech Sheet
Parts List
E4000 Configuration Program

Quick Start Guides

Operator Guide, LPG
Operator Guide, Refined Fuels, Preset Valve
Operator Guide, Refined Fuels, No Valve
Supervisor Guide →
Using the Configuration Program
USB Instructions

Flash Programming Software

How to Determine the Flash Version of the E4000 Main Board
RB Version – Instructions, programming application, and files
HEX Version – Instructions, programming application, and files

Serial Protocol


Neptune RML2000 Mass Flowmeter for Bobtails

The only truck-mounted mass flowmeter with over fifteen years of proven performance.

In 2002, we introduced the world’s first mass flowmeter designed to meet the rigorous demands of the LPG bobtail environment. Since then, the advantages of this all-electronic system have been proven again and again. With no moving parts to wear out, the RML2000 provides dependable, maintenance-free service. Discover how the unmatched accuracy and maintenance-free reliability of the Neptune RML2000 can increase your efficiency and profitability.


  • Improved accuracy eliminates unmetered product
  • Accuracy is not affected by temperature, pressure, density, or viscosity
  • Wider range – 100:1 turndown vs. 5:1 for mechanical meters
  • No moving parts – reduced downtime, longer service life, greater calibration stability
  • Reduced weight


Installation Manual
Tech Sheet
Why measure mass? View the mass flowmeter tutorial.
White paper: Mass Flow Metering for LPG Delivery