Contrec 202A User manual

202A-M-V3.1
FIELD MOUNTED
RATE TOTALISER
MODEL 202A
June 2017

202A-M-V3.1

202A-M-V3.1
CONTENTS
1. Introduction 3
1.1 Model Number Versions 4
1.2 Intrinsic Safety Approvals 6
1.3 Operation 7
2. Specification 8
3. Programming 10
3.1 Program Steps 11
3.2 Calculation of Rate and Total 14
3.3 Total Conversion 16
3.4 Filtering 17
3.5 Example 19
4. Signal Input 20
5. Alarm & Pulse Outputs 21
6. Intrinsic Safety Connections 23
7. Installation 25
7.1 Wall Mounting 25
7.2 Panel Mount Version 26
7.3 Removing the Front Panel 27
7.4 The Main Electronics 29
7.5 Wiring 30
7.6 Maintenance 30
7.7 Terminal Designations 31
Index 32

202A-M-V3.1

202A-M-V3.1
Introduction 3
1. INTRODUCTION
The Model 202Ai Rate-Totaliser is a microprocessor based instrument
designed to measure a 4-20mA signal from flowmeters and pressure
transducers. The
instrument can be programmed to display directly in engineering units and
includes features such as linear or square law calculation, integration and
digital filtering.
Rate, Total and Accumulated Total can be displayed in engineering units on
the large LCD display. A front panel switch selects the function for display
and a Reset button allows the Total to be reset to zero.
The instrument is fully programmable, with all calculation constants set via
the front panel switches and stored in a non-volatile memory which will
retain data indefinitely. The user can program span, filtering levels,
display resolution and cutoff point.
The instrument is powered from a 4-20mA input signal and therefore,
requires no external power.
The Model 202Ai Rate Totaliser conforms to the EMC-Directive of the Council
of European Communities 2004/30/EU, the LVD directive 2014/35/EU and the
following standards:
EN61326:2013 Electrical equipment for measurement, control
and laboratory use – EMC requirements :
Residential, Commercial & Light Industry
Environment & Industrial Environment.
EN61010:2010 Safety requirements for electrical equipment
for measurement, control, and laboratory use.
In order to comply with these standards, the wiring instructions in Section 7.5
must be followed.

202A-M-V3.1
4 Introduction
1.1 MODEL NUMBER VERSIONS
The Model Number describes the options available for the 202Ai as follows:
Model 202Ai . x
where x denotes the mounting options and will be replaced by one of the
following numbers:
0No holes drilled for cable entry
1Panel mount
2Wall mount (standard)
6for Pipe mounting
The Wall mount instrument is supplied with cable glands that are watertight
and have integral strain relief.
Approval Versions
C CSA USA / Canada Approval
M ATEX/IECEx Approval

202A-M-V3.1
Introduction 5
The Model 202A

202A-M-V3.1
6 Introduction
1.2 INTRINSIC SAFETY APPROVALS
The Model 202Ai is certified for use in hazardous areas and has IECEx, ATEX
and CSA U S/C approvals.
The Model 202Ai certification details are:
IECEx Approval IECEx BVS 15.0099X
Rating Ex ia llB T4 Gb
ATEX Approval BVS 15 ATEX E 106 X
Rating II 2G Ex ia IIB T4 Gb
Ambient Temperature: Maximum ambient temperature of 60°C.
CSA US/C Approval LR 104 840-5.
Type: Class 1, Groups C and D.
When installing in hazardous areas, the instrument must be installed
according to the guidelines in Section 2 and in accordance with the local
relevant standards for wiring and installation in hazardous areas.
4-20mA Input
The input can be connected to IS circuits with the following maximum values:
Ui = 28V
Ii = 93mA
Pi = 653mW
Relay Outputs
The outputs can be connected to IS circuits with the following
maximum
values:
Ui = 28V
Ii = 93mA
Pi = 653mW

202A-M-V3.1
7 Specification
1.3 OPERATION
The Model 202A Rate Totaliser will display:
Rate
Resettable Total
Accumulated Total
Both the Rate and Resettable Total are continuously displayed while
the Accumulated Total is only displayed when the ACCUM TOTAL key
is pressed.
The Resettable Total can be reset at any time by pressing the RESET key.
The instrument also has a test mode which can be entered by
simultaneously pressing all three front panel keys. The tests are as
follows:
Lo Test By pressing the ACCUM TOTAL key, the low alarm output will
go low.
Hi Test By pressing the RESET key, the high alarm output:
a. will go low if CAL00 = 0 (high alarm output),
b. will output 100ms pulses every 0.5sec if CAL00 = 1 (scaled
pulse output).
Display Test By pressing the PROGRAM key, all segments of the display will
show.
To exit the test mode, simultaneously press all three front panel keys.
Note that when the input signal drops below 3.75mA (4-20mA input), a signal
error will occur. The display will alternate between the current total and the
word "SIGNAL". When the input signal drops below≈3.5mA the Model 202A
shuts down saving totals in the non-volatile memory.

202A-M-V3.1
8 Specification
2. SPECIFICATION
General
Display: LCD, which is continuously powered.
Resettable Total: 7 digits with 10mm (0.4") high digits.
Resettable from front panel.
Accumulated Total: Displayed when the Accumulated Total button
is pressed.
Rate/Display: 5 digits with 8.5mm (0.33") high digits.
Span: The units of measure per timebase (eg. gallons/sec)
is programmable in the range 0.000001 to 999,999.
Decimal Points: Decimal Point positions are fully programmable
for both rate and total.
Timebase: Span can be programmed in units per second,
minute,hour or day.
Signal Type: 4-20mA.
4-20mA Input
Resolution and
Linearity: 0.05% of span.
Accuracy: 0.05% of span @ 25°C.
0.1% (typ) of span, full temperature
range.
Update Time: 0.5 seconds.
Connection: Two wire.
Voltage Drop: 2.5 volts maximum.