DL8000 Preset
Controller
The DL8000 Preset Controller is based on the popular and high performing ROC800- Seriesremote operations controller. This new design
delivers accurate measurement and reliable control, local or remote, via
Ethernet or serial (Modbus) communications.
The preset is capable of double-precision math. Computations are made in
accordance with Institute of Electrical and Electronic Engineers (IEEE)
standards and utilize double-precision floating point math to minimize
meter-to-meter differences, make volume corrections highly precise, and avoid
premature roll-over of totalizers.
Density Correction
The DL8000 accepts density signals as a
frequency, 4–20 mA, or through a communications
device. It accepts inputs from a flowing density
meter (such as a Solartron Frequency Densitometer
or a MicroMotion Coriolis meter). The DL8000
corrects observed density to standard conditions
and calculates the temperature and pressure
volume correction factors.
Temperature Compensation
The DL8000 can accept an input from an RTD, 4–
20 mA, or thermocouple device. It then calculates a
temperature volume correction factor in accordance
with industry-standards API MPMS Chapter 11.1
and ASTM-D1250 1980 and 2004 tables 5A, 5B,
5D, 6A, 6B, 6C, 6D, 23A, 23B, 23D, 24, 24A, 24B,
24C, 24D, 53A, 53B, 53D, 53E, 54A, 54C, 54D,
54E, 59A, 59B, 59D, 60A, 60B, 60D, ISO 91.1, ISO
91.2, GPA TP25 (1998), and GPA TP27 (draft).
Pressure Compensation
The DL8000 can accept a 4–20 mA signal from a
pressure transducer and compensate flow
calculations for volumetrics due to pressure in
accordance with the following standards and tables
API 11.2.1, 11.2.2, 11.2.1(M), and 11.2.2(M).
Pulse Fidelity
The DL8000 monitors dual pulse inputs for integrity
in accordance with ISO 6551-1982 and BS 6439:
1983 or API Petroleum Measurement Standard,
Chapter 5.5, level B and Institute of Petroleum
Standard, IP 252.76, Part XIII, Section 1, Level B.
Meter Factor Linearization
The DL8000 Preset can perform linearization of
meter factors and K factors using up to 12 points to
ensure accuracy over the entire range of flow.
Reporting
The DL8000 generates reports in compliance with
NIST Handbook 44 – 2006 Edition and 2003 Update
and NCWM Publication 14.
Other Features
- Archival storage of 450 alarms and 200
transactions with up to four batches each.
- Storage of the last 1000 weights & measures
events (in accordance with NIST Handbook 44).
- Integral Weights & Measures switch.
- Independent permissive sensing AC power.
- Digital valve control with automatic high flow
rate recovery.
- Independent temperature compensation
methods for individual products.
- Automatically sensing or user-entered values
for thermal expansion and linear equation.
- User-entered vapor pressure of light
hydrocarbons.
Operations – The DL8000’s user-friendly multilanguage
display prompts the operator through the
entire loading sequence, assuring a safe and
reliable loading operation. The loading sequence
starts after the operator connects the safety circuits,
selects a recipe, enters a preset quantity, and
presses the Start button. The DL8000 automatically
turns on the required product pumps and additive
injection equipment and opens the digital flow
control valves.
A low-flow start sequence can be initiated to reduce
static build-up when delivering petroleum products.
To keep loading time to a minimum, the DL8000
automatically maintains the highest possible flow
rate that the system can deliver. Three different flow
profiles for each recipe provide maximum system
flexibility regardless of the meter size. When certain
recipes require small percentages of one or more
components, you can configure the programmable
flow profiles to automatically deliver smallpercentage
component(s) only during the high flow
stage of the delivery, pulsing the smaller percentage
component(s) to maximize system performance.
As the end of the batch sequence approaches, the
component streams slow to a pre-defined lowflow/
stop flow rate. The high-speed digital valve
control algorithm, working in conjunction with the
linear digital control valve, ensures a smooth,
repeatable, low-flow stop and final stop without line
shock.
To assure product quality, you can program an
automatic single product line-flush sequence at the
end of the delivery to flush the loading arm with a
single base product. The DL8000 is equipped with
digital output circuits you can configure for
volume/pulse outputs for data acquisition type
devices.
Blend Recipes – DL8000 memory allows up to 30
blend recipes. Each recipe has individual totalizers
and is highly configurable, providing maximum
flexibility.
Linearization – Multi-point linearization is
programmable with up to 12 points. The DL8000
automatically interpolates between the 12 meter
factor setpoints to assure system accuracy over the
required flow ranges.
Alarms – The DL8000 offers comprehensive alarms
for blending systems. You can define each alarm
action for no action, display only, close relay
contact, stop loading process, or lock the unit. Builtin
programmable alarm conditions are also userselectable.
You can also configure the reference
base temperature for compensation corrections.
Data Communications – The DL8000’s base unit
has three built-in communication ports. The base
unit can support up to three additional ports (via
optional communications cards) for a total of six
ports. The base unit ports are:
- Local Operator Interface (RS-232D) – LOI.
- Ethernet – Comm1.
- EIA-232 (RS-232) – Comm2.
The Local Operator Interface (LOI) port’s standard
RJ-45 connector provides an EIA-232 (RS-232D)
link between the CPU and a PC. Use ROCLINK?
800 Configuration software to configure the CPU,
extract data, and monitor its operation. All DL8000
ports support Modbus slave protocol; master
protocol is supported on all but the LOI and Ethernet
ports.
Data Security – DL8000 data is secured with a 4-
digit user-defined access code. All calibration data
is secured with the access code and a wire-sealable
mechanical security switch that is integrally
mounted in the DL8000 keypad.
I/O Modules - The DL8000 supports a variety of
hot-pluggable I/O modules. You can add up to nine
optically isolated I/O modules as needed to satisfy a
wide variety of field I/O requirements. Available
modules include:
- Alternating Current Input/Output (AC I/O).
- Advance Pulse Module (APM) with
densitometer processing.
- Analog Inputs (AI).
- Analog Outputs (AO).
- Discrete Inputs (DI).
- Discrete Outputs (DO).
- Digital Relay Outputs (DOR).
- HART Input/Output.
- Pulse Inputs (PI) – High or Low speed.
- RTD Inputs (RTD).
Communications Modules – You can install up to
three additional communication modules in the
DL8000 to provide ports for communicating with a
host computer or other devices. The DL8000
accommodates the following module types, in any
combination:
- EIA-232 (RS-232).
- EIA-422/EIA-485 (RS-422/RS-485).
- Multi-Variable Sensor (MVS) interface.
- Dial-up modem.