Strata Technology DCP50 User manual

DCP50 User Manual
Strata Technology Limited
DCP50 High Precision Pump
User Manual
Part No. S000016.2

Page ii Part No. S000016.2 DCP50 User Manual
This manual is for use with MK2 pumps only i.e. pumps with the RS485 interface.

DCP50 User Manual Part No. S000016.2 Page iii
Important user information
It is essential that all users read this User Manual completely in order to fully understand the safe
use of the DCP50 High Precision Pump.
WARNING!
The WARNING! symbol shown here appears throughout the manual
and highlights instructions that must be followed by the user, otherwise
serious personal injury can occur. Wherever this sign appears, it is
important not to continue until the stated instructions have been fully
followed and are clearly understood.
CAUTION!
The CAUTION!sign appears wherever instructions are given in the manual that must be
followed to avoid damage to the product or other equipment. It is important not to continue until
the stated instructions have been fully followed and are clearly understood.
Note
The Note sign appears in the manual where information relating to trouble-free and optimal use
of the pump appears.
CE Certifying
This product meets the requirements of applicable CE-directives. A copy of the corresponding
Declaration of Conformity is shown at the rear of this User Manual.
The CE symbol and corresponding declaration of conformity is valid for the instrument when it is:
– used as a stand-alone unit, or
– connected to other CE-marked equipment and
– used in the same state as it was delivered from Strata Technology Ltd.
This is a Class A product for laboratory use only. In a domestic environment this product may
cause radio interference in which case the user may be required to take adequate measures.

Page iv Part No. S000016.2 DCP50 User Manual
Should you have any technical queries regarding this product, or have any comments to make
regarding this manual, we will be pleased to receive them at:
Strata Technology Limited
Strata House
Batavia Road
Sunbury-on-Thames
Middlesex
TW16 5LR
United Kingdom
Telephone: [phone]
Strata Technology Limited reserves the right to make changes in the specifications without prior
notice.
Warranty and Liability
Strata Technology Limited guarantees that the DCP50 has been thoroughly tested in accordance
with our procedures to ensure that it meets its published specifications. The warranty included in
the conditions of delivery is valid for 13 months from the date of shipping, and only applies if the
DCP50 has been installed and used according to the instructions provided in this User Manual.
The ‘standard’ DCP50 uses 316 grade stainless steel and Nitronic 60 wetted parts. For pumps
being used with corrosive solvents e.g. brine, a version of pump is available with Hastelloy wetted
parts which must be requested when ordering. If a ‘standard’ pump is returned for a warranty
repair, and the fault is found to be due to a corrosive solvent having been used, this will
invalidate any warranty placed upon it and the full cost of repair will be chargeable.
Strata Technology Limited will in no event be liable for incidental or consequential damages,
including without limitation, lost profits, loss of income, loss of business opportunities, loss of use
and other related exposures, however caused, arising from the faulty and incorrect use of this
product.
The only user serviceable parts of the DCP50 are located behind the plastic cover as described in
Chapter 7. The warranty is invalidated if the end user attempts to open the DCP50 case. The
warranty also applies to the external power supply, which is also invalidated if it is damaged by
the end user and any attempt made to repair it.
The DCP50 contains a 3V lithium button cell to maintain the real-time clock within the pump,
which should last for 25 years. This is not a user changeable part, and in the unlikely event that it
requires replacing, the pump must be returned to Strata Technology Ltd. to be changed.

DCP50 User Manual Part No. S000016.2 Page v
Trademarks
DCP50 is a registered trademark of Strata Technology Limited.
Recycling
This symbol indicates that waste electrical and electronic equipment (WEEE) must
not be disposed of as unsorted municipal waste, but must be collected separately
by an authorised body. This product contains a single Lithium button cell. Please
contact Strata Technology Ltd. for information concerning the decommissioning of
equipment.
Copyright©2016 Strata Technology Limited. All rights reserved. No part of this publication may
be reproduced, stored in a retrieval system or transmitted in any form or by any means, without
permission in writing from Strata Technology Limited.

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DCP50 User Manual Part No. S000016.2 Page vii
Table of Contents
Chapter 1 Introduction .........................................................................................................1
Chapter 2 Specifications .......................................................................................................3
Chapter 3 Unpacking............................................................................................................5
Chapter 4 Description...........................................................................................................7
4.1 Front Cover..............................................................................................................7
4.2 Front Panel Controls and Indicators...........................................................................7
4.3 Pump Options ..........................................................................................................9
4.4 Fluid Delivery...........................................................................................................9
4.5 Switchover Valve......................................................................................................9
4.6 Rinsing System ......................................................................................................10
4.7 Pressure Sensor .....................................................................................................10
4.8 Tubing Connectors .................................................................................................11
4.9 Rear Panel.............................................................................................................11
4.10 Solvent Change Control ..........................................................................................13
4.11 Pulse Compensation ...............................................................................................13
4.12 Run Control ...........................................................................................................13
4.13 Pressure Safety Limit Control ..................................................................................14
4.14 Flow Rate/Pressure Control.....................................................................................14
4.15 DCP50 Menu System ..............................................................................................15
Chapter 5 Installation.........................................................................................................17
5.1 Operating Environment...........................................................................................17
5.2 Tubing...................................................................................................................17
5.3 Start-up Procedure.................................................................................................19
5.4 Priming the Rinsing System.....................................................................................20
5.5 Draining the pump .................................................................................................21
Chapter 6 Operation...........................................................................................................23
6.1 Operating Mode .....................................................................................................23
6.2 Routine Operation..................................................................................................24
6.3 Pressure Calibration................................................................................................25
6.4 Bulk Modulus Setting..............................................................................................25
6.5 PID Controller ........................................................................................................26
6.6 Solvents.................................................................................................................27
6.7 Pump Head Cleaning ..............................................................................................28
6.8 Operating at Low Temperatures..............................................................................28
Chapter 7 Maintenance and Servicing..................................................................................29
7.1 Piston Seal Adjustment...........................................................................................29
7.2 Piston Seal Replacement.........................................................................................31
7.3 Glass Tube Replacement.........................................................................................35

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7.4 Rinsing Washer Replacement..................................................................................35
7.5 Transfer Port Replacement......................................................................................36
7.6 Cylinder Adjusting Screw Replacement ....................................................................37
7.7 Tubing Replacement...............................................................................................37
7.8 Updating Firmware.................................................................................................39
7.9 Returning the DCP50 for Service/Repair...................................................................39
7.10 Recycling...............................................................................................................39
Chapter 8 Troubleshooting .................................................................................................41
8.1 Fault Finding..........................................................................................................41
Chapter 9 Spare Parts and Accessories................................................................................45
9.1 Piston Assembly.....................................................................................................45
9.2 Tubing Fittings.......................................................................................................45
9.3 Tubing...................................................................................................................45
9.4 Miscellaneous Items ...............................................................................................45
9.5 Accessories............................................................................................................45

Introduction Chapter 1
DCP50 User Manual Part No. S000016.2 Page 1
Chapter 1 Introduction
The Strata Technology Limited DCP50 is a high precision dual-cylinder pump for use in laboratory
applications where constant flow at pressures up to 50 bar (5 Mpa, 725 psi) or constant pressure
up to 50 bar is required. The DCP50 is very accurate and reproducible, especially at low flow
rates over the whole pressure range. The pump’s design is such that it has excellent chemical
resistance.
The DCP50 operates by the use of two alternating pistons connected to a switchover valve via
1/16” tubing. While one piston is pumping solvent out, the other piston is drawing more solvent
in. At the end of piston travel, the direction is reversed and the valve changes over the tubing
connections to allow output flow to continue.
The flow rate/set pressure and pressure limit are easily and precisely set using front panel rotary
controls, with the desired settings shown on a liquid crystal display (LCD). As various solvents
with different bulk compressibility can be used with the pump, a ‘Bulk Modulus’ value can be set
using the same controls via a menu screen.
The wetted metal parts of the standard pump are made from 316 grade stainless steel and
Nitronic60. A version of pump with Hastelloy wetted parts can be ordered if working with
corrosive solvents e.g. brine. A rinsing system is fitted as standard, which feeds rinsing solution
between the two cylinders behind the piston heads to clean the internal surface of the glass
tubes during use. Although use of the rinsing system is optional, it is recommended for pumps
being used with corrosive solvents.
The DCP50 is provided with USB and RS485 interfaces allowing remote control of the pump and
data gathering, using software available for purchase from Strata Technology Limited via the
website www.stratatec.co.uk. Firmware updates for the pump are free, and can be programmed
via the USB interface. Refer to the website for details as they become available.
The DCP50 operates from an external 24V DC supply provided by a desktop style power supply.
The output lead of the power supply is fitted with a plug that locks into the mating socket on the
pump ensuring that it cannot be accidentally pulled out during operation.
WARNING! When using the pump with hazardous chemicals, take
suitable protective measures, such as wearing gloves that are resistant
to the chemicals being used, and wearing protective safety glasses.
Follow local regulations and instructions for safe operation and
maintenance of the pump and any equipment connected to it.
WARNING! The tubing to the Switchover Valve is pre-installed on the
DCP50, except for the inlet connection. It is important to note that if
changing the existing tubing as part of the maintenance routine, the
tubing is connected to the correct ports otherwise the pump will not
operate correctly and could put the user at risk.

Chapter 1 Introduction
Page 2 Part No. S000016.2 DCP50 User Manual
WARNING! If the DCP50 pump is used in a manner not specified by
Strata Technology Limited, protection against personal injury inherent in
the equipment’s design can be rendered ineffective.

Specifications Chapter 2
DCP50 User Manual Part No. S000016.2 Page 3
Chapter 2 Specifications
Flow Rate ranges 1-500ml/hour variable in steps of 1ml/h.
0.01 – 5.00ml/hour variable in steps of 0.01ml/hour
Constant Pressure range 0.1 – 50.0 bar in steps of 0.1 bar
Operating pressure 0-50 bar (725psi) for all flow rates
Flow rate accuracy ± 1.5% of setting or ± 0.5ml/hour (whichever is greater)
independent of back pressure
Reproducibility Better than 0.5% of set flow rate or pressure.
Flow rate precision Better than 1% with the same solvent and temperature.
Bulk Modulus Adjustable from 0.5 to 2.5 in 0.01 steps
Materials of wetted parts Fluoroplastics (PTFE, ETFE, FEP, Tefzel, Teflon), PEEK, stainless
steel, Nitronic 60, Hastelloy (optional when ordering), and
borosilicate glass.
Pressure read out 0-50.5bar
Pressure limit Protective shutdown, adjustable in the range 0 – 50.5bar in 0.1bar
steps
Drive DC Stepper motor
Maximum speed of piston
travel 1.77mm/sec
PC Interface Pump control, programming and data transfer via the following
connectors
•USB – Type B connector
•RS485 – 9-way D-type male connector
Power supply Input voltage : 100 - 240 V~, frequency 50/60 Hz
Input current : max 1.7A @ 100V
Output voltage : 24V DC
Output current : 2.71A
Power consumption <24VA
Environment +4°C to +40°C, 20–95% relative humidity, 84–106kPa (840–
1060mbar) atmospheric pressure.
Dimensions 410 x 203 x 172 mm.
Weight 10.2kg

Chapter 2 Specifications
Page 4 Part No. S000016.2 DCP50 User Manual
Compliance with standards The declaration of conformity is valid for the instrument only if it is:
•used in laboratory locations
•used in the same state as it was delivered from Strata
Technology Ltd.
Safety standards This product meets the requirement of the Low Voltage Directive
(LVD) 2006/95/EC through the following harmonized standards:
•IEC 61010-1: 2010 edition 3 including Cor 1: 2011 and
Cor 2: 2013 Including all published deviations for Europe,
USA and Canada
EMC standards This device meets the requirements of the EMC Directive
89/336/EEC through the following harmonized standards:
•CENELEC EN 61326-1 (emission and immunity)
•EN 61000-3-2:2006 +A1:2009 +A2:2009
•EN61000-3-3:2013
This device complies with part 15 of the FCC CFR47 rules
(emission).
Operation is subject to the following two conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received,
including interference that may cause undesired operation.

Unpacking Chapter 3
DCP50 User Manual Part No. S000016.2 Page 5
Chapter 3 Unpacking
Open the packing box carefully, and unpack the DCP50 pump and accessories, checking the
contents of the box against the packing list supplied with it (also shown below).
CAUTION! The DCP50 has a weight of 10.2kg and care should be taken when lifting it. The
pump should be lifted by placing the fingers under the unit at each end of the metal case and
lifting. Never attempt to lift the pump by use of the plastic cover!
Save the foam insert packing material and the box as a precaution in the event that the pump
needs to be returned to Strata Technology Limited. Check the DCP50 for any visible signs of
damage that may have occurred during transit.
CAUTION! The system should be unpacked and left for 24 hours in case any condensation builds
up inside the pump due to low temperatures it may have been subjected to during transit.
CAUTION! The system should be installed on a stable laboratory bench providing a suitable
working area.
Place the DCP50 on the bench. Before operating the pump for the first time, carefully read
Chapter 5 of this manual.
Note that there may be some water remaining in the glass tubes and the tubing that was used
during the test and calibration routines. This will be flushed through once the pump is operating.
Packing List (also supplied separately)
Item Description Quantity
1 DCP50 Pump 1
2 Mains lead 1
3 Desktop power supply 1
4
Tubing kit comprising the following.
•1/16” inlet tubing – 500mm long
•1/8” outlet tubing – 500mm long
•Nut and ferrule for 1/16” tubing
•Nut and ferrule for 1/8” tubing
1
5
Tool kit comprising the following.
•¼” Vici socket wrench
•1.5mm Hex key
•2.5mm Hex key
•4mm Hex key
•5mm/4mm open ended spanner
1

Chapter 3 Unpacking
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Description Chapter 4
DCP50 User Manual Part No. S000016.2 Page 7
Chapter 4 Description
4.1 Front Cover
The DCP50 is fitted with two types of covers at the front (not shown in Figure 1). Metal guards
are fitted over both piston rods to cover the two openings in the front of the pump to prevent the
risk of operator fingers getting trapped in the mechanism, and to reduce the risk of solvent
spillage entering the pump.
The outer cover is plastic and this fits over the whole of the piston assembly to protect the user
from breakage of the glass tubes resulting from incorrect handling. It is held in position by four
screws. Transparent windows in the cover allow a full view of the pistons in operation.
4.2 Front Panel Controls and Indicators
Please refer to figure 1.
Item No. Description Function
1 Solvent Change Button/Indicator Use this button when wanting to change
solvent as it speeds up flushing of the
pump. The button has a red LED indicator
to show that this feature is enabled.
Details are provided in section 4.10.
2 Pulse Compensation Button/Indicator Use this button when running the DCP50
with a back pressure of 5 bar or above.
Operation is indicated by a yellow LED
within the button. Details are provided in
section 4.11.
3 Run Button/Indicator Use this button to operate the pump.
Operation is indicated by a green LED
within the button. Details are provided in
section 4.12.
4 Pressure Transducer This monitors the output flow from the
pump and feeds a signal back to the
internal control circuit.
5 6-port Switchover Valve The valve is connected to the pistons, and
switches the direction of flow around the
tubing system when the pistons change
direction to ensure continuous output
flow. Solvent input and output are also
routed via this valve.
6 Over Pressure Indicator This red LED indicates when the output
pressure has exceeded the limit set by
the rotary control. Pump operation stops
when this happens.

Chapter 4 Description
Page 8 Part No. S000016.2 DCP50 User Manual
Item No. Description Function
7 Pressure Safety Limit Control This control sets the maximum pressure
that the pump will operate at. Details are
provided in section 4.13.
8 Liquid Crystal Display (LCD) Shows the flow rate, back pressure, and
the set pressure limit when running in
Constant Flow mode, or set pressure,
flow rate and set pressure limit when
running in Constant Pressure mode. It will
also show the menus for other features
when selected as described in this User
Manual.
9 Flow Rate/Pressure Control This control sets the flow rate of the
pump when in Constant Flow mode, and
sets the required pressure when in
Constant Pressure mode. Details are
provided in section 4.14.
10 Power Switch Switches power to the internal circuitry of
the pump when turned on. =Off, l=On
Figure 1 - DCP50 Front Panel with protective covers removed
1 2 3 4 5 6 7 8 9 10
Transfer Glass Piston Tubing Cylinder adjusting
Port Tube Connections screw

Description Chapter 4
DCP50 User Manual Part No. S000016.2 Page 9
4.3 Pump Options
The DCP50 can be supplied in two variants, which must be specified when ordering. The standard
option uses stainless steel and Nitronic60 for the parts that come into contact with the solvents
used. For users wishing to use corrosive solvents such as brine, the DCP50 can be supplied with
Hastelloy wetted parts. Apart from the piston seal retainer (see section 4.4) which is user
serviceable, the Hastelloy parts have to be fitted during manufacture.
4.4 Fluid Delivery
The DCP50 operates by the use of two alternating pistons fitted in high precision borosilicate
glass tubes which are mounted at the front of the pump. The pistons are attached to the arms of
a carrier mounted on a lead screw which is driven by a stepper motor via a toothed belt. The
driving mechanism is located behind the front panel with only the carrier arms protruding through
it. The pistons act in a reciprocating fashion so that as one piston is expelling solvent, the other
piston is drawing in more solvent. At the end of travel, an opto-switch sends a signal to the
micro-controller on the internal control board which then briefly stops the motor and operates the
switchover valve. Following a successful switch, a signal is sent from the valve to the micro-
controller which then reverses the direction of rotation of the drive motor and starts it running
again, so that the full cylinder is now pumping out solvent and the empty one is drawing solvent
in. This process then repeats when piston travel reaches the other end.
Each piston consists of four parts; the piston seal retainer, the piston seal, the piston washer and
the piston rod (see Figure 2). The piston seal is tensioned by adjustment of the piston rod which
is screwed onto the piston seal retainer. This causes the piston seal located between the piston
seal retainer and the piston washer to expand outwards to seal against the wall of the glass tube.
Figure 2 - Piston Assembly
4.5 Switchover Valve
The six port valve shown in Figure 1 and Figure 3 is a self-contained motorised rotary valve
controlled by the internal circuitry of the pump. The valve has six tubing connections; one for the
solvent input, one for solvent output, and four which are attached to the transfer ports mounted
at the end of the pistons. The DCP50 is supplied with the 1/16” tubing already attached between
the transfer ports and the switchover valve. Tubing to connect to the input and output ports is
supplied in a kit with the pump, along with the necessary fittings.
A diagram showing how the tubing is attached and how the solvent flow is routed is shown in
Figure 3.
Piston rod
Piston washer
Piston seal
Piston seal retainer

Chapter 4 Description
Page 10 Part No. S000016.2 DCP50 User Manual
Figure 3 - Solvent Flow Diagram (including optional rinsing system)
In the configuration shown, the left piston is drawing in solvent via ports 3 and 2 of the
Switchover Valve. Port 1 is blocked off by the Switchover Valve, so there is no flow in that
segment of tubing. At the same time, solvent already in the right hand cylinder is pumped out via
ports 5 and 6 of the Switchover Valve and then through the Pressure Sensor. Port 4 is blocked off
so there is no flow in that segment of the tubing.
At switchover time, ports 3 and 4 and ports 1 and 6 are linked, and ports 2 and 5 are blocked off.
As the pistons move in the opposite direction, solvent is drawn in by the right piston via ports 3/4
and pumped out of the left piston via ports 1/6. A return signal from the Switchover Valve is sent
to the control board indicating a successful switchover. If this is not received, the driver motor
stops running to prevent pressure being built up in the pump by a cylinder attempting to pump
into a sealed port.
Note
Do not run the pump for long periods of time without any solvent/cleaning solution. The
polymeric components within the switchover valve require being wetted to continue functioning
correctly.
4.6 Rinsing System
The rinsing system (also shown in Figure 3) comprises the ‘rinsing washers’ fitted between the
ends of the glass tubes and the central support, joined by a short length of flexible tubing. The
system is initially primed by loading one of the cylinders with the rinsing solution behind the
piston head. As the pump operates, the rinsing solution is passed between the two cylinders via
the flexible tube to clean the internal surface of the glass. As the rinsing solution becomes
contaminated, it can be pumped out and then replaced with new solution. It is recommended
that the rinsing solution is replaced on a daily basis.
4.7 Pressure Sensor
The pressure sensor shown in Figure 1 and Figure 3 is connected to the output from the
switchover valve and consists of a diaphragm with a four-active-arm strain gauge bridge. The
diaphragm expands or contracts with variations in pressure causing the resistance in the bridge
arms to change. This gives a signal output proportional to the pressure being applied. This signal
is amplified and fed to the micro-controller circuit on the control board.

Description Chapter 4
DCP50 User Manual Part No. S000016.2 Page 11
The sensor and associated circuitry have two main functions; the first is to continuously measure
the operating pressure of the solvent pumped through it, and the second is to check that if the
pressure exceeds the limit set on the front panel, the micro-controller turns off the drive motor
and illuminates the Over Pressure indicator. Instructions for setting the pressure limit are given in
Chapter 5.
When running in Constant Pressure mode, the output from the pressure sensor is continuously
monitored and a PID Controller adjusts the flow rate accordingly to maintain constant pressure.
4.8 Tubing Connectors
The 1/16” diameter tubing used within the DCP50 is pre-fitted with nuts and ferrules and is
connected between the transfer ports on the pistons, the switchover valve, and the pressure
sensor.
The tubing kit supplied with the pump comprises the following.
•500mm length of 1/16” inlet tubing and a stainless steel nut with ferrule for connection
between the DCP50 and the solvent reservoir.
•500mm length of 1/8” outlet tubing and a plastic nut with a two part ferrule (metal and
plastic) for connection between the DCP50 and the laboratory equipment.
4.9 Rear Panel
The rear panel of the DCP50 has three connectors – DC Power, USB and RS485. The USB and
RS485 interfaces provide serial communications with a PC for configuring the pump remotely and
for gathering data using software available for purchase from Strata Technology Ltd. Either
interface can be used, the only restriction being the length of the cable.
4.9.1 DC Connector
The circular DC connector at the rear of the DCP50 has three pins, the smallest of which is not
used. The other two pins are for the +24V DC input and the 0V connection. The pin-out of this
connector is shown in Figure 4.
The plug of the external power supply is attached to the DC connector on the rear panel. The
plug has a locking mechanism to prevent the power lead being pulled out accidentally.
0V
(Pin 2)
+24V
(Pin 1)
Figure 4 - DC Connector Pin-out (as viewed from rear of pump)

Chapter 4 Description
Page 12 Part No. S000016.2 DCP50 User Manual
4.9.2 USB Connector
The USB interface provides serial communication with a PC for remotely configuring the pump
and for gathering data. It can also be used for field upgrades to the operating firmware of the
pump. It is recommended that the USB cable length is kept to 3 metres or less.
This is a standard USB-B connector, the pin-out of which is shown in Figure 5.
4.9.3 RS485 Connector
The RS485 interface also provides serial communications with a PC but can be used over much
greater distances than USB, with the only limitation being that data transfer becomes slower with
a longer cable. The interface is configured for full-duplex data transmission. To calculate the
transfer rate, divide 108by the cable distance in metres, with the result being in bit/s e.g. a 50m
cable would transfer data at 2Mbit/s.
The pin-out for this connector is shown in Figure 6
Figure 6 - RS485 Connector Pin-out (viewed from rear of pump)
Pin No. 1 4 5 8 9
Function GND RXD+ RXD- TXD+ TXD-
Figure 5 - USB Connector Pin-out (viewed from rear of pump)
Pin 1 : +5V
Pin 4 : 0V
Pin 2 : Data -
Pin 3 : Data +