GDS C1 User manual

P/N 1200-0620-46
GDS Corporation
1245 Butler Road League City, Texas 77573
[phone] [phone] (Fax) www.gdscorp.com
INSTRUCTION MANUAL
MODEL C1 PROTECTOR 8/16 CHANNEL CONTROLLER
(Revision 4.6 – Firmware 6.03 & later, including Wireless Setup)
Warning:
Read & understand contents of this manual prior to operation. Failure to do so
could result in serious injury or death.

P/N 1200-0620-46
GDS Corporation
1245 Butler Road League City, Texas 77573
[phone] [phone] (Fax) www.gdscorp.com
SECTION 1...........................................................................................................1
IMPORTANT SAFETY ISSUES .......................................................................................1
1.0 GENERAL DESCRIPTION..................................................................................2
1.1 DATA DISPLAY SCREENS...............................................................................2
1.1.1 TREND SCREEN.......................................................................................................... 3
1.1.2 BAR GRAPHS SCREEN............................................................................................... 3
1.1.3 COMBINATION SCREEN............................................................................................. 3
1.2 SPECIFICATIONS:..............................................................................................4
1.2.1 DC POWER SUPPLY REQUIREMENTS ..................................................................... 4
1.2.1a 150 WATT AC – 24VDC POWER SUPPLY.................................................................. 4
1.2.2 RELAYS ........................................................................................................................ 4
1.2.3 AMBIENT TEMPERATURE RANGE ............................................................................ 4
1.2.4 HUMIDITY RANGE ....................................................................................................... 4
1.2.5 ALTITUDE..................................................................................................................... 4
1.2.6 HOUSINGS ................................................................................................................... 4
1.2.6a NON-INTRUSIVE MAGNETIC KEYPAD ...................................................................... 5
1.2.7 APPROVALS................................................................................................................. 5
SECTION 2...........................................................................................................5
2.0 BASIC OPERATION ...........................................................................................5
2.1 SETUP MENU CONFIGURATION......................................................................6
2.1.1 CHANGING MENU VARIABLES USING THE KEYPAD.............................................. 6
2.2 CHANNEL CONFIGURATION MENUS..............................................................7
2.2.1 CHANNEL SETUP ENTRY MENU ............................................................................... 8
2.2.2 ALARM 1 / ALARM 2 / HORN RELAY SET-UP MENU ................................................ 8
2.2.3 ALARM 3 / FAULT ALARM MENU................................................................................ 9
2.2.4 DATA FROM? MENU TO SET INPUT SOURCE ......................................................... 9
2.2.4a MIN / MAX RAW COUNTS MENUS ........................................................................... 10
2.2.4b MARKER MENUS....................................................................................................... 11
2.2.4c SENSOR LIFE DETECTION....................................................................................... 11
2.2.5 LINEARIZATION MENU.............................................................................................. 12
2.2.6 CONFIGURE MENU ................................................................................................... 12
2.2.6a EUNITS / MEASUREMENT NAME ASCII DATA FIELDS.......................................... 13
2.2.6b INPUT MEASUREMENT RANGE............................................................................... 13
2.2.6c DECIMAL POINT RESOLUTION................................................................................ 13
2.2.6d TURNING OFF UNUSED CHANNELS....................................................................... 13
2.2.6e COPY DATA TO?........................................................................................................ 13
2.2.7 CAL MODE.................................................................................................................. 14
2.3 SYSTEM CONFIGURATION MENUS...............................................................15
2.3.1 COMMON ALARM RELAYS 1 & 2.............................................................................. 15
2.3.2 10-0195 DISCRETE RELAY “FAILSAFE” MODE....................................................... 16
2.3.3 COMMON HORN RELAY & LOCAL PIEZO............................................................... 17
2.3.4 COMM PORT MENUS................................................................................................ 18
2.3.4a MASTER PORT RADIO SETUP MENU ..................................................................... 18
2.3.5 EIGHT / SIXTEEN CHANNEL MODES....................................................................... 19
2.3.6 SENSOR INFORMATION........................................................................................... 19
2.4 AUTHORIZATION MODE .................................................................................20
2.5 LCD CONTRAST ADJUSTMENT.....................................................................20

SECTION 3.........................................................................................................21
3.0 MAIN I/O INTERFACE PCB # 10-0142............................................................21
3.1 INPUT / OUTPUT OPTIONAL PCB’s ..............................................................22
3.1.1 OPTIONAL ANALOG INPUT PCB # 10-0158............................................................. 22
3.1.2 OPTIONAL DISCRETE RELAY PCB # 10-0195 ........................................................ 24
3.1.3 OPTIONAL *BRIDGE SENSOR INPUT BOARD #10-0191........................................ 25
3.1.4 CATALYTIC BEAD SENSOR INITIAL SETUP ........................................................... 26
3.1.5 OPTIONAL RTD / 4-20mA ANALOG INPUT BOARD # 10-0170............................... 27
3.1.6 OPTIONAL 4-20mA ANALOG OUTPUT BOARD #10-0167....................................... 29
3.1.7 OPTIONAL CLOCK / PRINTER INTERFACE BOARD # 10-0229 ............................. 30
3.1.7a CLOCK / PRINTER SYSTEM SET-UP MENU............................................................ 31
3.1.8 OPTIONAL 24VDC 150 WATT POWER SUPPLY ..................................................... 32
SECTION 4.........................................................................................................32
4.0 SYSTEM DIAGNOSTICS ..................................................................................32
SECTION 5.........................................................................................................35
5.0 MODBUS RS-485 PORTS ................................................................................35
5.1 MODBUS SLAVE REGISTER LOCATIONS.....................................................35
SECTION 6.........................................................................................................39
6.1 C1PM PANEL / RACK MOUNT ENCLOSURE.................................................39
6.2 C1N4 NEMA 4X WALL MOUNT FIBERGLASS ENCLOSURE.......................40
6.3 C1SS NEMA 4X WALL MT 316 STAINLESS STEEL ENCLOSURE..............42
6.4 C1XP NEMA 7 EXPLOSION-PROOF WALL MOUNT ENCLOSURE.............42
6.5 C1 MAIN I/O & OPTION PCB FOOTPRINT DIMENSIONS.............................43
SECTION 7.........................................................................................................45
7.0 ADDING THE 10-0288 RADIO MODEM “WIRELESS” OPTION....................45
7.1 10-0288 RADIO SETUP MENU........................................................................45
7.2 WIRELESS RECEIVER MODE........................................................................46
7.2.1 RADIO STATUS ALARMS - WIRELESS RECEIVER MODE..................................... 47
7.3 WIRELESS MODBUS SLAVE MODE..............................................................48
7.4 WIRELESS MODBUS MASTER MODE ..........................................................48
7.5 ANTENNA SELECTION....................................................................................48
7.5.1 DIPOLE AND COLLINEAR ANTENNAS..................................................................... 48
7.5.2 YAGI ANTENNAS ....................................................................................................... 49
7.5.3 MOUNTING NEAR OTHER ANTENNAS.................................................................... 49
7.5.4 COAX CABLES ........................................................................................................... 50
7.6 SURGE PROTECTION & GROUNDING...........................................................50
7.6.1 ANTENNA GROUNDING............................................................................................ 50
Connections to other equipment................................................................................................ 51

C1 Controller Users Manual
Revision 4.6
1
SECTION 1
IMPORTANT SAFETY ISSUES
The following symbols are used in this manual to alert the user of important instrument
operating issues:
WARNINGS:
Shock Hazard - Disconnect or turn off power before servicing this instrument.
NEMA 4X wall mount models should be fitted with a locking mechanism after
installation to prevent access to high voltages by unauthorized personnel (see
Figure 6.2).
Only the combustible monitor portions of this instrument have been assessed by
CSA for C22.2 No. 152 performance requirements.
This equipment is suitable for use in Class I, Division 2, Groups A, B, C, and D or
non-hazardous locations only.
WARNING- EXPLOSION HAZARD- SUBSTITUTION OF COMPONENTS
MAY IMPAIR SUITABILITY FOR CLASS I, DIVISION 2.
WARNING- EXPLOSION HAZARD- DO NOT REPLACE FUSE UNLESS
POWER HAS BEEN SWITCHED OFF OR THE AREA IS KNOWN TO BE
NON-HAZARDOUS.
WARNING- EXPLOSION HAZARD- DO NOT DISCONNECT
EQUIPMENT UNLESS POWER HAS BEEN SWITCHED OFF OR THE AREA
IS KNOWN TO BE NON-HAZARDOUS.
Use a properly rated CERTIFIED AC power (mains) cable installed as per local
or national codes
A certified AC power (mains) disconnect or circuit breaker should be mounted
near the controller and installed following applicable local and national codes. If
a switch is used instead of a circuit breaker, a properly rate CERTIFIED fuse or
current limiter is required to installed as per local or national codes. Markings for
positions of the switch or breaker should state (I) for on and (O) for off.
Clean only with a damp cloth without solvents.
Equipment not used as prescribed within this manual may impair overall safety.
!
This symbol is intended to alert the user to the presence of important
operating and maintenance (servicing) instructions.
This symbol is intended to alert the user to the presence of
dangerous voltage within the instrument enclosure that may be
sufficient magnitude to constitute a risk of electric shock.
!

2
1.0 GENERAL DESCRIPTION
The GDS Corp. C1 Sixteen Channel Controller is designed to display and control alarm
event switching for up to sixteen sensor data points. It may also be set as an eight
channel controller for applications needing fewer inputs. Alarm features such as ON and
OFF delays, Alarm Acknowledge, and a dedicated horn relay make the C1 well suited for
many multi-point monitoring applications. Data may be input to the C1 by optional
analog inputs or the standard Modbus® RTU master RS-485 port. A Modbus RTU slave
RS-485 port is also standard for sending data to PC’s, PLC’s, DCS’s, or even other C1
Controllers. Options such as analog I/O and discrete relays for each alarm are easily
added to the addressable I2C bus. Option boards have 8 channels and therefore require 2
boards for 16 channel applications.
In addition to traditional analog and serial methods of providing monitored values, the C1
is also capable of sending and receiving wireless data as described in section 7 of this
manual.
A 240 x 128 pixel graphic LCD readout displays monitored data as bar graphs, trends and
engineering units. System configuration is through user friendly menus and all
configuration data is retained in non-volatile memory during power interruptions. The
C1 front panel is shown below in Figure 1.0 displaying the 8 channel bar graph screen.
Additional data screens are shown in Figure 2.0.
Figure1.0
1.1 DATA DISPLAY SCREENS
The C1 Controller offers 3 distinct graphic displays for depicting the monitored data.
These are Bar Graphs, 24 Hour Trend and Combination. Each is shown in Figure 2.0.

C1 Controller Users Manual
Revision 4.6
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1.1.1 TREND SCREEN
The C1 Trend screen shown in Figure 2.0 displays a 24 hour trend of input data for the
channel selected. Horizontal tic marks are each hour and vertical tic marks are each 10%
of full scale. Dashed lines indicate alarm levels. The graphic LCD is 240 pixels wide so
each pixel represents 1/10 hour, or 6 minutes worth of data. The trend is 100 pixels high
so each represents 1% of full scale in amplitude. Since each data point must be collected
for 6 minutes before it may be displayed, it is likely input values will fluctuate during this
interval. Therefore, MAX, MIN and AVERAGE values are stored in RAM memory for
each 6 minute subinterval. To accurately portray the trend, a vertical line is drawn
between MIN & MAX values for each 6 minute subinterval. The AVERAGE value pixel
is then left blank, leaving a gap in the vertical line. This is demonstrated in the noisy area
of the 24 hour trend in Figure 2.0. If the MAX & MIN values are within 2% of each
other there is no need for the vertical line and only the AVERAGE value pixel is
darkened as in the quiet areas.
The top portion of each trend screen indicates channel #, real time reading in engrg. units,
measurement name, range, and MIN, MAX & AVERAGE values for the preceding 24
hour period. The SI field on the top right indicates number of seconds remaining in the
current 6 minute subinterval.
1.1.2 BAR GRAPHS SCREEN
The C1 Bar Graphs screen shown in Figure 2.0 allows all active channels to be viewed
simultaneously. Both engineering units values and bar graph values are indicated in real
time. Lines across the bars indicate the alarm trip points making it easy to identify
channels at or near alarm. A feature in the Systems menu tree allows new alarms to
always force the LCD to the bar graphs screen. This is useful for applications requiring
channels with alarms to be displayed.
1.1.3 COMBINATION SCREEN
The C1 Combination screen shown in Figure 2.0 offers a view of a single channel but
displays the data as a 30 minute trend, bar graph and large engineering units. It is also
useful for testing inputs for stability since MAX, MIN & AVERAGE values refresh each
time this screen is selected. For example, to test stability over a one hour period for an
input, begin timing as soon as the channel is selected. One hour later record the MAX,
MIN & AVERAGE values. The difference between MAX & MIN indicates peak to peak
excursions over the one hour period and AVERAGE is the average for the hour. Longer
or shorter tests may also be run. The numeric value shown below the bar-graph indicates
number of minutes samples have been taken. After 999 minutes the AVERAGE buffer
overflows and the error message UPDATE appears in the AVERAGE field. Exiting this
screen resets the buffer and clears the error message.

4
1.2 SPECIFICATIONS:
1.2.1 DC POWER SUPPLY REQUIREMENTS
Standard C1 power requirements are 10-30VDC @ 3 watts applied to terminals 9 & 11 of
TB2 on the standard I/O PCB (see section 3.0). Optional features increase power
consumption as described below:
Discrete Relay PCB option; add 2 watts per PCB (assumes all 8 relays are energized).
Analog Input PCB option; add 1/2 watt.
4-20mA Output PCB option; add 1 watt.
Catalytic Bead Sensor Input option; add 12 watts max (assumes maximum sensor
power consumption).
TB2 terminals 10 & 12 of the standard I/O PCB provide a maximum of 500mA fused
output power for powering of auxiliary external devices such as relays, lamps or
transmitters. Power consumed from these terminals should be considered when
calculating system power consumption.
1.2.1a 150 WATT AC – 24VDC POWER SUPPLY
*110-120 VAC @3.2A max
*220-240VAC @ 1.6A max
* A slide switch on the front of the power supply selects AC input range.
The 10-0172 150 watt power supply (Figure 3.8) is for powering the C1 and up to 16
detectors. A minimum of 5 watts per channel is available for powering of external
transmitters.
1.2.2 RELAYS
Common relays are standard and menus provide voting logic for ALARM 1,
ALARM 2, FAULT and HORN. Discrete relays are optional. All relays are rated
at 5 Amp for 28 VDC and 250 ~VAC RESISTIVE loads.
IMPORTANT: Appropriate diode (DC loads) or MOV (AC loads) snubber
devices must be installed with inductive loads to prevent RFI noise spikes. Relay wiring
should be kept separate from low level signal wiring.
1.2.3 AMBIENT TEMPERATURE RANGE
-25 to 50 degrees C
1.2.4 HUMIDITY RANGE
0 TO 90% R. H. Non-Condensing.
1.2.5 ALTITUDE
Recommended up to 2000 meters
1.2.6 HOUSINGS
*General purpose panel mount weighing 7 lbs and including hardware for 19” rack
mounting (Figure 6.1).
*NEMA 4X wall mount in fiberglass enclosure weighing 17 lbs (Figure 6.2).
!

C1 Controller Users Manual
Revision 4.6
5
*NEMA 7 wall mount suitable for DIV 1&2 Groups B,C,D weighing 110 lbs (Figure
6.4).
*Includes non-intrusive magnetic keypad.
1.2.6a NON-INTRUSIVE MAGNETIC KEYPAD
The C1 operator interface includes five front panel touch keys. A magnetic keypad
option offers these five keys with adjacent magnetic keys. This option is included as a
standard feature. It is useful in applications where it may be inconvenient to open the
enclosure’s door to access the touch keypad.
1.2.7 APPROVALS
CSA C22.2 No 1010.1 and ISA S82.02; CSA C22.2 No 152 for combustibles; UL 1604 /
C22.2 No 213 (Div 2 Groups A,B,C,D); EN55011 & EN61000 (CE Mark). CSA File # =
219995 and may be seen at: CSA-International.org.
SECTION 2
2.0 BASIC OPERATION
The C1 offers 3 graphic screens for viewing monitored data and a Set-Up menu screen
for operator interface to configuration menus. They are shown below in Figure 2.0. The
Bar Graphs screen allows viewing of all active channels simultaneously. The Trend
screen displays a 24 hour trend one channel at a time. The Combination screen displays a
bar graph, large engineering units and a 30 minute trend one channel at a time. Input
channels may be displayed in sequence with the UP/DOWN keys. The NEXT key
switches between the 3 graphic data screens. When C1 power is applied, the graphic
LCD returns to the screen active when power was last removed.
Setup menus are entered by pressing EDIT from any data screen, and scrolling to the
desired menu using the UP/DOWN keys. Pressing EDIT again enters the selected
menu’s tree of variables. This Setup mode may be exited manually by pressing NEXT,
or automatically when no keys are pressed for 5 minutes. Alarm relays and front panel
alarm LED indicators remain active during the Setup mode. An AUTHORIZE menu
offers a password feature to prevent tampering with C1 parameters.

6
Figure 2.0
2.1 SETUP MENU CONFIGURATION
Variables inside system and channel menu trees allow optimum C1 configuration for a
wide range of demanding multi-point monitoring applications. Access to menus is via
the Setup mode by pressing EDIT and activating the Setup screen shown in Figure 2.0.
Menu trees are provided for each of the 16 channels and another for system variables.
Select the desired menu by scrolling with UP/DOWN and EDIT to enter the menus.
2.1.1 CHANGING MENU VARIABLES USING THE KEYPAD
Upon entering a menu, a pointer controlled by the UP/DOWN keys indicates the selected
variable. Some are simple YES/NO or ON/OFF entries toggled by pressing the EDIT
key. Others, such as Measurement Name and Eunits fields may have many ASCII
character possibilities. Allowed ASCII characters are as follows:
ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz blank space
!"#$%&`()*+,-./0123456789:;<=>?@. EDIT places a cursor over the item and
UP/DOWN scrolls through each allowed entry. The NEXT key moves the cursor to the
next position within a field. When the field is complete, EDIT clears the cursor and
loads it into non-volatile memory where it is retained indefinitely. With no cursor
present, NEXT closes open menus in reverse order and returns the LCD to the most
recent data display.

C1 Controller Users Manual
Revision 4.6
7
2.2 CHANNEL CONFIGURATION MENUS
Figure 2.1 illustrates the menu tree for configuring Channel variables. These items affect
only the specific channel selected. System specific variables are in the menu tree shown
in section 2.3.
Figure 2.1

8
2.2.1 CHANNEL SETUP ENTRY MENU
The entry menu shown on the left side of Figure 2.1 allows access to all configuration
variables for the selected channel. These are, Alarm 1, Alarm 2, Alarm 3, Data
From? Linearize, Configure and Calibrate.
2.2.2 ALARM 1 / ALARM 2 / HORN RELAY SET-UP MENU
Alarms 1 and 2 are identical except A1 may not be acknowledged and front panel LED
indicators are yellow while A2’s are red. Since their configuration menus are the same
only one is shown in Figure 2.2 for clarity.
Figure 2.2
The first entry determines the Setpoint value where the alarm trips. It is entered in
engineering units. For example, if a channel monitors 0-50 ppmH2S and the alarm must
trip at 10 ppm, the correct entry is 10.00.
Latching determines either manual or automatic alarm reset operation. YES
requires a manual Alarm Reset to unlatch the alarm even though an alarm condition
no longer exists. YES also causes this alarm group’s common relay, front panel
LED, and optional discrete relay to latch. NO allows all outputs for this alarm to
automatically reset as soon as the alarm condition clears.
TRIP ON. is set to HIGH for increasing alarms or LOW for decreasing alarms to
determine if the alarm activates upon exceeding or falling below the setpoint.
The ON DELAY / OFF DELAY entries allow ON and OFF time delays affecting
how long the setpoint must be surpassed before an alarm event transition occurs. ON
delays are limited to 10 seconds while OFF delays may be as long as 120 minutes.
Delays are useful in many applications to prevent nuisance alarms and unwanted
cycling into and out of alarm conditions.
The HORN ON entry allows linking this alarm to the common horn relay. NO
causes the alarm to have no effect upon the horn relay. Entering YES causes this
alarm to turn the horn relay on steady, or, to pulse it depending upon horn
configuration in they system menu (see section 2.3.1).
Discrete LED indicators on the front panel indicate the status of each alarm and relay.
Any new alarm event causes the associated LED to flash until Alarm Reset occurs
causing an acknowledged steady on condition. Operators should recognize new alarms
by a flashing LED. Alarm Reset also acknowledges, or deactivates, the horn relay until
another new alarm occurs.
All relays are rated at 5 Amp for 28 VDC and 250 ~VAC RESISTIVE loads.
IMPORTANT: Appropriate diode (DC loads) or MOV (AC loads) snubber devices
!

C1 Controller Users Manual
Revision 4.6
9
must be installed with inductive loads to prevent RFI noise spikes. Relay wiring should
be kept separate from low level signal wiring.
2.2.3 ALARM 3 / FAULT ALARM MENU
The discrete channel alarms identified as Alarm 3/Fault may be configured either as a 3rd
level alarm, or, as a Fault alarm indicating the input is out of range in the negative
direction. When used as a level alarm, features such as on / off delays, latching, and trip
direction are also available. It is important to understand that though discrete channel
alarms (LED’s & optional discrete relays) may be set as Alarm 3 level alarms, the
common relay for this group is always a Fault alarm. The fault out of range threshold for
the channel is the most recent Fault trip point entered prior to changing the menu to
Alarm 3. The following example describes how to configure both the Fault out of range
and Alarm 3 level trip points for a channel. Example: If the common Fault relay must
trip as the input falls below negative 10% of full scale, and, the discrete alarms trip as the
input exceeds a level, then the –10% Fault setpoint must be entered first. Toggle the
TYPE menu entry to FAULT and enter –10.00% into the setpoint entry. Next, toggle the
menu back to LEVEL and enter the desired Alarm 3 level setpoint. The -10% Fault
value is retained in memory even though it no longer appears on the menu.
Figure 2.3
2.2.4 DATA FROM? MENU TO SET INPUT SOURCE
Channels may be independently configured to accept input data from the following
sources (also see Figure 2.4):
An analog input PCB attached to the I2C bus.
A sensor input PCB attached to the I2C bus.
The Modbus RS-485 master port connected to modbus slave devices.
Note: Each Modbus menu selection also requests the RTU # and the Alias
register # location of the data to be retrieved from the RTU. Alias register
numbers define the location of the variable representing the input value and must
be obtained from the manufacturer of the Modbus RTU device.
Our 10-0288 Radio Modem may be connected to the Modbus RS-485 master port
to enable wireless communication to GASMAX ECX wireless sensor
transmitters.
EDIT toggles the Data From: entry between Analog, Analog with Local Cal or Sensor
Direct, WIRELESS RF900 and Modbus RTU (signed, unsigned & floating point).

10
Analog should be selected when the channel’s input comes from a transmitter or
monitoring device with a calibrated output such as 4-20mA. Analog with Local Cal is
available when the C1 will be the point of calibration for the analog input. Sensor Direct
is identical to Analog with Local Cal and both activate the C1’s Cal Mode features (see
section 2.2.7). Problems may arise if calibrations are performed in two places upon the
same signal so Cal Mode menus are only visible when Sensor Direct or Analog with
Local Cal is selected. These selections should only be used when the input originates
from a non-calibrated signal source such as the Bridge Sensor Input option described in
section 3.1.3, or, our ST-49 Transmitter with a non-calibrated 4-20mA output. These
applications require the C1 to be used as the calibration point since the sensors have no
zero or span controls.
Figure 2.4
2.2.4a MIN / MAX RAW COUNTS MENUS
The Min Raw and Max Raw counts entries included in Input Data From: menus define
the range of input counts that provide Measurement Range read-out values described in
section 2.2.6b. This menu entry is determined by the A/D converter resolution of the
channel’s input. For example, if the input is a 10 bit Modbus® device with zero at 200
counts and 100% at 1000 counts, then this menu’s MIN should be set at 200 and MAX at
1000. If communicating with the C1’s optional 12 bit Analog Input PCB the MIN should
be 800 and the MAX 4000.
If the input device’s resolution is unknown, the live counts variable on the bottom of the
screen displays actual raw A/D counts currently being read by this channel. This reading
may be used to test the input device for what A/D counts are provided for zero and 100%
if these values are unknown. Forcing the input device to read zero should provide the
A/D counts value needed to make this channel’s display also read zero. Likewise,
forcing the input device to read 100% should provide the A/D counts value needed to
make the C1 channel’s display also read 100%.
If Modbus 32 BIT is selected, a Byte Order entry appears at the bottom of the menu.
This determines WORD and BYTE alignment of data at the remote Modbus transmitter
when sending its 4 byte IEEE Floating Point values. With the pointer on this entry, the

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EDIT key toggles between the 4 possible modes. Min / Max Raw values are not used in
this mode.
Note: Each Data From: item has a matching default Min/Max counts value of 20% to
100% with ± 5% over/under range applied. If the default value is incorrect for the input
device it should be edited.
2.2.4b MARKER MENUS
Some transmitters or monitoring devices providing C1 inputs also indicate special modes
of operation, such as Calibration, Maintenance or Fault, by transmitting a special <4mA
or negative “Marker” value. The C1 offers channel Marker menus for detecting and
indicating such events (see Figure 2.5). While active, the C1diplays a 6-digit ASCII
message to indicate the special event and if equipped with 10-0167 4-20mA output
option, the C1 also transmits the same <4mA value.
Marker Enabled turns the marker feature ON and OFF
The negative Marker value is entered into the Marker % field as a negative percent
of full scale. For example, -15.62% of full scale detects a marker value of 1.5mA
(1.5mA is -15.62% of full scale when 4-20mA is the range).
The Mark As menu allows user entry of the 6-digit ASCII message to be displayed
when the marker is detected.
Figure 2.5
2.2.4c SENSOR LIFE DETECTION
Sensor Life should only be activated when the Marker event is Calibration and when a
sensor life value is transmitted after each calibration. This feature is provided primarily
for use when interfacing the C1 to R. C. Systems’ GASMAX ECX Sensor Transmitters
which may be configured to transmit sensor life values after each calibration (see Figure
2.6). For Sensor Life to record properly the monitor must perform as follows: After the
Calibration Marker interval, 4.0mA transmits for 10 seconds to indicate its calibration
mode is complete. The monitor then transmits between 4.0mA and 5.0mA for five
seconds depending on remaining sensor life where 4.0mA = 0% and 5.0mA = 100%
remaining sensor life. The C1 reads this value and records it as the channel’s Sensor
Life. Sensor Life is stored in the C1 modbus database and displayed as a bar-graph in
the Sensor Info screen (see section 2.3.6). It is a useful tool for planning sensor
replacement schedules.

12
Figure 2.6
2.2.5 LINEARIZATION MENU
The linearization menu allows each channel to have its own linearization curve stored in
the controller’s non-volatile memory. Input versus output points must be entered in
percent of full scale values. This means if the range is 0-200 ppmH2S then 100 ppm is
50% of full scale. Zero input will provide a zero output and 100% input a 100% output.
Nine intermediate points may be entered to define the curve.
EDIT
NEXT
Entry menu
Channel XX
Measurement Name
Linearization menu
Channe l XX
Linear izat i on
%I n p ut %Out put
10 . 0 0
20.00
30.00
40.00
50.00
60.00
70.00
80.00
90.00
10 . 0 0
20.00
30.00
40.00
50.00
60.00
70.00
80.00
90.00
Al ar m 1
Al ar m 2
Al ar m 3
Dat a Fr o m
Cal i br at e
Li near i ze
Conf igur e
Figure 2.7
2.2.6 CONFIGURE MENU
From the entry level setup menu in Figure 2.8 the CONFIGURE menu may be entered
for setting variables defining how the controller presents monitored data to the various
graphic displays.
Entry menu
Channe l XX
Me a s u r e me n t Na me
Al ar m 1
Al ar m 2
Al ar m 3
Dat a Fr om
Cal i br at e
Li near ize
Con f i gur e
EDIT
NEXT
Input / Copy To: menu
Channel XX
CONFIGURATION
Measur ement Name
Euni t s
Zer o
Span
De c i ma l Poi n t s
PCTLEL
0.000
Copy Now?
10 0 . 0
Channel On? 0 YES
Copy To XX
Figure 2.8

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2.2.6a EUNITS / MEASUREMENT NAME ASCII DATA FIELDS
The first two items in this menu are for entering the 6 character engineering unit and 16
character Measurement Name ASCII fields. Eunits should define the units of measure for
what this channel is to display. Measurement Name should describe the source of this
data in the user’s terminology. Section 2.1.1 of this manual describes how to use the
front keypad to modify these fields.
2.2.6b INPUT MEASUREMENT RANGE
The ZERO / SPAN entries allow configuration of the measurement range displayed by
this channel. Measurement Range works along with A/D Counts menus, described in
section 2.2.4a, to define the range of the input signal’s engineering units. For example, if
a channel’s input is 4-20mA from a transmitter monitoring 0 to 10ppm chlorine, then the
Zero value should equal 0.000 and the Span value equal 10.00. The six ASCII
engineering units previously entered are automatically displayed at the top of each menu
as a reminder. Four digits must appear in this entry so trailing 0’s may appear here that
are not displayed on other data screens.
2.2.6c DECIMAL POINT RESOLUTION
Resolution of displayed channel values is configured in this menu by setting the number
digits trailing the decimal point. Values are limited to a maximum of four digits, and a
polarity sign. An auto-ranging feature displays the highest resolution allowed by this
menu’s decimal point entry. For example, if three decimal points are entered, and the
range is 0 to 100ppm, the reading will be 0.000 at 0ppm and 100.0 at 100ppm. However,
this may be undesirable due to the high resolution at zero unless the sensor’s output is
extremely stable. If decimal points are limited to one, the 0ppm reading becomes 0.0 and
the 100ppm reading remains 100.0. Resolution may be limited further by setting decimal
points to 0. In the above example, this would cause 0ppm to display 0and 100ppm to
display 100.
2.2.6d TURNING OFF UNUSED CHANNELS
The Channel On? entry determines if this channel is to be utilized. Turning it off will
cause the controller to never process inputs applied to this channel and no alarms will be
tripped or data displayed. Inactive channels have a line drawn through them on the Setup
screen as indicated by channels 15 & 16 in Figure 2.0. If less than 9 channels are to be
activated, the C1 may be set for 8 channel mode, deactivating channels 9-16. This is
done in the System Setup menu described in section 2.3. The C1 will only allow 15
channels to be turned off. At least one channel must remain on
2.2.6e COPY DATA TO?
This menu simplifies the Setup procedure by allowing similar channels to be copied from
one to another. For example, if all channels are identical except for the Measurement
Name entry, channel 1 could be configured and copied to channels 2 – 16. Only
Measurement Name then must be configured on channels 2 – 16. Use EDIT to increment
channel numbers and UP/DN to point to Copy Now? Press EDIT once more to copy.

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2.2.7 CAL MODE
IMPORTANT! Each channel’s CALIBRATION menu is inactive unless it’s Input
Data From: menu, described in section 2.2.4, is set for Analog with Local Cal or Sensor
Direct. C1 CAL MODE features allow pushbutton calibration of zero and span values.
This feature should be utilized only when there are no other zero/span controls within the
monitoring system since it is inappropriate to calibrate a signal at more than one point.
Therefore, if calibration is to be performed at another transmitter or monitoring device,
the C1 CAL MODE feature should not be used.
The CALIBRATION MENU allows entering the correct Cal ZERO & Cal SPAN set-
point values needed to calibrate the sensor. These are entered in the same engineering
units as input range. Set Zero &Set Span controls in this menu allow pushbutton
calibration by moving the pointer to each and pressing the EDIT key. A live reading of
the channel’s value allows calibration checks to see if an adjustment is needed.
Unintentional calibrations are reset by the Unity Gain menu item. Unity Gain resets
zero offset to 0 and span gain to 1. It is useful for returning the calibration to a known
starting place. Sensor aging may be monitored by recording zero and span readings at
Unity Gain when it is new, and again at later dates when degradation may have
occurred.
To check zero calibration, apply the ZERO calibration value to the sensor and observe
the live reading. If the zero reading differs from the zero setpoint, a calibration is needed.
To calibrate zero, move the pointer to Set Zero and press EDIT. A warning message
explains that pressing EDIT again will change the zero calibration and any other key will
exit. The procedure for span calibration is identical. For example, if an LEL combustible
sensor is to be spanned with 50% LEL span gas, the span set-point must be 50%. If 45%
LEL is to be used later, the span set-point must be changed to 45% to match the span
calibration gas. If the reading is only 40% LEL with the 50% gas applied a span
calibration is needed. Move the pointer to the Set Span entry and press EDIT twice.
Unity Gain may be used at anytime to cancel incorrect calibrations and start again.
Figure 2.9

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2.3 SYSTEM CONFIGURATION MENUS
Some items needing configuration are not specific to a channel but affect the entire C1
system. These are located in the system entry menu shown on the left side of Figure
2.10. System menus are accessed by pointing to the desired item and pressing EDIT.
Figure 2.10
2.3.1 COMMON ALARM RELAYS 1 & 2
READ THIS SECTION CAREFULLY AND TEST ALL SETTINGS BY
SIMULATING C1 INPUT CONDITIONS THAT SHOULD ACTIVATE
THESE ALARM RELAYS!
Common Relay 1 & Common Relay 2 menus are identical and therefore discussed
only once. It is very important to fully understand these menus since they determine the
functions of each common relay.
!