Brasch Gdcp-touch User manual

GDCP-Touch

Installation / Operation Manual

Brasch Environmental Technologies, LLC

40 Long Road, Suite 0

Chesterfield, Missouri 63005

3 4-29 -0440

www.braschenvtech.com

Table of Contents
Introduction...................................................................................................................................5
General Description..................................................................................................................5
Features and Benefits..............................................................................................................6
Technical Specifications................................................................................................................7
Product Specifications..............................................................................................................7
Target Gas Specifications.........................................................................................................8
Carbon Monoxide.................................................................................................................8
Nitrogen Dioxide...................................................................................................................8
Operation Safety Notice................................................................................................................9
Types of Notices.......................................................................................................................9
Quick Start Guide....................................................................................................................... 0
Step   – Mounting.................................................................................................................. 0
Step 2 – Input Wiring.............................................................................................................. 0
Step 3 – Remote Transmitter Wiring...................................................................................... 
Step 4 – Relay Wiring............................................................................................................. 
Step 5 – External Alarms........................................................................................................ 2
Step 6 – Applying Power........................................................................................................ 2
Step 7 – Testing the System................................................................................................... 2
Installation................................................................................................................................... 3
Mounting the Control Panel.................................................................................................... 3
Mounting the Transmitters...................................................................................................... 3
Connecting the Power Supply................................................................................................ 5
Connecting the Remote Transmitters..................................................................................... 6
Connecting the Ventilation System......................................................................................... 7
Connecting the External Alarm............................................................................................... 8
Connecting the Voltage or Current Proportional Output........................................................ 8
Applying Power For the First Time......................................................................................... 8
Performing a System Test...................................................................................................... 9
Typical Installation Diagrams..................................................................................................20
Operation....................................................................................................................................23
How the Transmitter Senses the Target Gas.........................................................................23
How the Panel Controls the Ventilation Equipment...............................................................23
Sensors..............................................................................................................................23
Relays................................................................................................................................23
Zones..................................................................................................................................24
Overrides............................................................................................................................24
Analog Output....................................................................................................................24
Modbus Output...................................................................................................................24
BACnet IP Output...............................................................................................................24
Navigating the User Interface.................................................................................................25
Home Screen.....................................................................................................................25
Zone Screen.......................................................................................................................26
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Relay Screen......................................................................................................................26
Passcode Entry Screen......................................................................................................27
Settings Menu....................................................................................................................27
Factory Default Settings.........................................................................................................28
Adjusting the Hardware Settings............................................................................................29
Changing the Sensor Address...........................................................................................29
Changing the Relay Board Address...................................................................................29
Changing the Analog Output Scale....................................................................................29
Adjusting the Software Settings.............................................................................................30
Adding/Removing Sensors.................................................................................................30
Adding/Removing Relays...................................................................................................30
Adding/Removing Zones....................................................................................................3 
Adjusting the Setpoints......................................................................................................3 
Adjusting the Delays..........................................................................................................32
Adjusting the Activation Type.............................................................................................32
Adjusting the Zone Display Type........................................................................................33
Assigning Sensors.............................................................................................................33
Assigning Relays................................................................................................................34
Assigning Analog Outputs..................................................................................................34
Changing Relay Levels......................................................................................................35
Setting Manual Overrides...................................................................................................36
Setting Automatic Overrides...............................................................................................37
Changing the Date and Time.............................................................................................37
Configuring BACnet...........................................................................................................38
Performing a Reset............................................................................................................38
Using the Analog Outputs.......................................................................................................39
Obtaining the Best Operation.................................................................................................40
Carbon Monoxide and/or Nitrogen Dioxide Transmitters...................................................40
Maintenance...............................................................................................................................4 
Testing the Response to the Target Gas................................................................................4 
Carbon Monoxide and/or Nitrogen Dioxide Transmitters...................................................4 
Replacing the Sensor.............................................................................................................42
Suggested Repair Parts.........................................................................................................43
Troubleshooting..........................................................................................................................44
Error Messages......................................................................................................................44
Relay # – Manual Override Active......................................................................................44
Sensor # Communication Loss..........................................................................................44
Sensor # – Calibration Expired..........................................................................................44
Sensor # End of Life – Please Replace.............................................................................44
Sensor # Sensor Missing...................................................................................................45
Sensor # Calibration Invalid...............................................................................................45
Relay Board # Communication Loss..................................................................................45
Insert SD Card....................................................................................................................45
SD Write Error – Replace SD Card....................................................................................45
Checking and Replacing the Battery......................................................................................46
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Checking and Replacing Fuses..............................................................................................46
Common Installation/Operation Mistakes..............................................................................47
Ventilation Components Connected to the Wrong Relays.................................................47
Relay Levels Set Incorrectly...............................................................................................47
Improper Communication Wiring.......................................................................................47
Setpoint Level Set at Wrong Concentration.......................................................................47
Delay Period Set Incorrectly...............................................................................................48
Setting the Proportional Output Incorrectly........................................................................48
Bias/Termination Switches in the Wrong Position..............................................................48
Relay Activation Type Set Incorrectly.................................................................................49
Panel Not Grounded..........................................................................................................49
Transmitter Mounted in an Unsatisfactory Location..........................................................49
Limited Warranty.........................................................................................................................50
Warranty Statement...........................................................................................................50
Service and Repair Procedures.........................................................................................50
Appendix.....................................................................................................................................5 
Models and Descriptions........................................................................................................5 
Transmitter Model and Description....................................................................................5 
Accessory Model Number and Description........................................................................5 
Figures and Diagrams............................................................................................................52
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Introduction

General Description

The Brasch Environmental Technologies GDCP-Touch Gas Detector Control Panel is designed

to function as a complete ventilation control system. These systems can be as simple as a

panel and one transmitter controlling one ventilation fan, or as complex as a panel with 28

sensors controlling 32 zones worth of ventilation equipment.

The control panel itself consists of a touchscreen display, a relay control board, and digital

control circuitry. The panel monitors the signal from the transmitters, compares the signal to

preset values, and controls relay contacts based upon the comparison. These relay contacts

then provide signals that control ventilation components such as exhaust fans, louvers, and

dampers. The touchscreen provides a visual indication of the system’s operational condition

along with an intuitive interface for configuring the entire system. A linear proportional output is

also included for communication with a building management system (BMS), direct digital

controls system (DDCS), or variable-frequency drive (VFD).

The sensors used in the remote transmitters operate on the electrochemical principle and are

able to detect carbon monoxide or nitrogen dioxide. A current is produced when the target gas

reacts chemically with an electrode inside the sensor. This small current is converted to an

analog voltage, amplified, and converted to a digital signal. This signal is proportional to the

gas concentration present at the sensor and is shown on the display. After comparing the

digital signal to preset values, the panel updates the display and relays.

The GDCP-Touch housing has a NEMA 4X rating and is supplied with knockouts so that the

control panel can mount directly to a standard four inch conduit box. A hinged cover secured

by two screws makes it easy to gain access to the touchscreen for system configuration. A

secondary, interior hinge affords access to the relay board, allowing power, communication,

and relay connections to be made.

The GDCP-Touch can also accept additional relay boards in the form of GDCP-

ExpansionPacks. These provide four more relays for added control along with another analog

output and a signal repeater to extend the range and sensor capacity. GDCP-PowerPacks

may be added to convert AC line voltage to the low voltage required to power the control

panel, transmitters, and relay boards.

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Features and Benefits

•Limitless Possibilities

◦Fully Configurable Zones, Relays, Setpoints, Delays, and Outputs

◦Scalable System Size via Relay Expansion Packs

•Increased Control

◦On-Demand Ventilation Control by Gas Concentration, Timer Schedule, or User

Input

◦7” Full-Color LCD Touch Screen

•Maximum Detection

◦Monitors up to 28 CO and/or NO2 Sensors

◦Each Sensor Covers up to 9,000 sq. ft.

•Enhanced Durability

◦NEMA 4X Water and Dust Resistance

•Intelligent Connectivity

◦BACnet IP and Modbus RTU Communication for BMS Interfacing

•Simplified Installation

◦Customized Factory Programming and Configuration for Every Job

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Technical Specifications

Product Specifications

Input Power 24 VAC, 50/60 Hz, 0.75 A

Optional: 20 VAC, 50/60 Hz, 0.3 A via GDCP-PowerPack

Installation Category II (local level, over-voltage transients less than 500V)

Storage Temperature -50°C to 20°C (-58°F to 248°F)

Operating Temperature -20°C to 70°C (-4°F to 58°F)

Humidity 0% to 90% (non-condensing)

Ventilation Control Relays 25 VAC, 50/60 Hz, 5 A resistive, 250 VA inductive

Relay Capacity 4 internal, up to 32 total relays via GDCP-ExpansionPacks

Sensor Capacity Up to 30 remote sensors

Optional: Up to 28 remote sensors via GDCP-ExpansionPacks

Zone Capacity Up to 4 zones

Optional: Up to 32 zones via GDCP-ExpansionPacks

Internal Alarm 70 dB @ 0 cm, 2.9 kHz piezoelectric element

Display 7.0” LCD, 024 x 600, 5-point capacitive touch

Analog Outputs User-selectable 4-20 mA, 0.2- VDC, -5 VDC, or 2- 0 VDC

Digital Outputs BACnet IP, Modbus RTU

Alert Levels 4 levels, fully adjustable

Delay Times 0 to 599 minutes, separate settings for entrance and exit

Dimensions 8. 5” W x 9.93” H x 2.70” D (2 cm W x 25 cm H x 7 cm D)

Weight 5.0 lbs (2.27 kg)

Housing Gray, NEMA 4X, fiberglass/polycarbonate

Compliance Pending

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Target Gas Specifications

Remote transmitters for this control panel are available for monitoring carbon monoxide and/or

nitrogen dioxide as target gases. Regulatory agencies have determined the threshold

concentrations at which the gases become dangerous. Brasch Environmental Technologies,

LLC has designed their transmitters so that the measurement ranges for each target gas meet

the agencies’ requirements. Each target gas, for which Brasch currently produces a

transmitter, is listed below along with the relevant concentration specifications.

Carbon Monoxide

Full Scale Span: 200 PPM

Resolution: PPM

Minimum Accuracy*: ± 0% or 6 PPM

Relay Setpoints 0-200 PPM (in increments of .0 PPM)

Expected Lifespan 0 years

Recommended

Recalibration Time 2 years

Nitrogen Dioxide

Full Scale Span: 0 PPM

Resolution: 0. PPM

Minimum Accuracy*: ± 5% or 0.8 PPM

Relay Setpoints 0- 0 PPM (in increments of 0. PPM)

Expected Lifespan 0 years

Recommended

Recalibration Time 2 years

*Allowable tolerance for accuracy and repeatability criteria as defined in Annex A, Item 2 of ANSI/ISA 92.00.0 -20 0 (R20 5)

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Operation Safet Notice

Certain procedures and operations detailed in this manual require that specific precautions be

taken prior to beginning the procedure or operation. When precautions are required, a notice

will be printed in an appropriate location in the manual. The user is urged to read and

understand all such notices.

T pes of Notices

Three types of notices may be used in this manual to describe the severity of the situation

encountered.

WARNING: This notice indicates that conditions exist that could cause personal injury

or loss of life.

CAUTION:Conditions exist that could cause damage to the equipment or other

property.

Note: Special consideration should be given to the procedure or operation,

otherwise an unexpected operational result could occur.

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Quick Start Guide

Please read this entire manual before attempting to install and operate this control panel. This

guide is only intended to provide the basic steps necessary for installation and operation.

Each step will reference the portion of the manual where more complete information can be

obtained.

Step 1 – Mounting

Determine the location for mounting your panel and transmitters. The locations may be

indicated on the architectural drawing. Also, the owner or designer of the facility may be

consulted. Mounting guidelines can be found on page 3 of this manual.

Step 2 – Input Wiring

Provide a dedicated circuit at the required 24 VAC operating voltage at each panel mounting

location. Follow all national and local wiring codes. A conductor connected to earth ground

should also be provided. The circuit must include a disconnect switch located within easy

reach of the panel.

Ensure that the step-down transformer provides the correct secondary voltage and has the

necessary volt-amp rating to power each component in the system. Each control panel

requires 0.75 VA, each transmitter requires 2.4 VA, and each expansion pack requires 0.4 VA.

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WARNING

This control panel may require the use of voltage levels high enough to cause fatal injuries.

Proper procedures must be followed any time work is performed on this unit.

Only qualified personnel should attempt to install, maintain, or service this equipment.

CAUTION

Operating these devices with the incorrect voltage and power requirements can cause

internal electrical components to overheat and fail. Operation with the wrong power

requirement will void the manufacturer’s warranty and the installer will be responsible for any

damage that occurs.

Contact Brasch Environmental Technologies, LLC before connecting power to the control

panel or transmitters if you are unsure of the correct power requirement.

Connect the incoming power conductor to 8-24VAC, the return conductor to 8-24RET, and

the ground conductor to the green screw.

Refer to page 5 for further information.

Step 3 – Remote Transmitter Wiring

The control panel does not supply power to the remote transmitters. However, power may be

daisy chained through the control panel to the transmitters. Use a two-conductor cable with

color-coded conductors of at least 8 AWG to connect the power. Use a shielded, twisted-pair

cable with color-coded conductors of at least 24 AWG to connect communication. A single

four-conductor cable may be used but will reduce the maximum distance the system can

cover. See figure 0 on page 53 for details. If possible, choose cables with color-coded

conductors that follow the suggested color scheme listed on the drawings.

The transmitters will be shipped with four color-coded wires exiting the top of the housing

through a conduit fitting. If you have chosen color-coded conductors that match the wire

colors, connect the cable conductors to the wires of the same color. If your cable conductors

do not match the wire colors, assign a cable conductor color to each wire and make a list of

this assignment. Follow this color assignment when connecting any other transmitters in the

system. All transmitters share the same conductors back to the panel. Therefore, a four-

conductor cable can be connected from transmitter to transmitter, or from transmitter to panel,

as the situation dictates. Follow the wiring diagrams on page 2 and 22 to determine the

proper connections at the panel.

Step 4 – Rela Wiring

The relay board inside the control panel has four relays with connections for both normally

open (NO) and normally closed (NC) operation. These connection points are labeled on the

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CAUTION

It is very important that the power and signal connections between each transmitter and

between the transmitters and the control panel be correct. If the connections are wired

incorrectly, damage to both the transmitters and the control panel will occur.

Use a cable with color-coded conductors and make sure that the same conductor connects

to the same terminal on each transmitter and the control panel.

Do not apply power to the transmitter or control panel unless you are sure that the

connections are correct.

silkscreen next to the terminal blocks as well as in the diagram on page 54. The relay state is

labeled for the physical state of the relay when the control panel is not powered. In the default

configuration, all relays will operate independently of one another. To use multiple-speed fans,

you will need to assign different relay levels in the settings and invert the wiring connections to

avoid damaging ventilation equipment.

Do not exceed the specified voltage and power limits of the relays (see page 7). Most

installations require motor starters or larger relays to provide the necessary power

requirements for the ventilation components.

For more information concerning ventilation system operation, read page 7 of this manual.

Step 5 – External Alarms

Determine if the installation requires an external alarm. If so, provide the proper wiring and

connect the wires to the required voltage source. Any relay may be used to trigger an external

alarm. To synchronize the internal control panel alarm with external alarms, make sure the

setpoints and delay times are the same in both the Zone Settings Screen and Relay Settings

Screen.

Refer to page 8 for more information concerning the alarm feature.

Step 6 – Appl ing Power

Once you are sure that the wiring connections are correct, apply power to the control panel

circuit. When power is first applied to the transmitters, they will begin a 50 second warm-up

period. During this time, the control panel will display “--” in place of gas concentration values

on the Zone Screen and Relay Screen. Once the warm-up has finished, the gas concentration

values will appear.

See page 8 for more information concerning the initial startup.

Step 7 – Testing the S stem

The manual overrides on this control panel can be used to open and close the relays to verify

that ventilation and warning equipment is connected properly. This feature can be accessed

from the individual Relay Settings screens.

Page 9 contains a more complete procedure for testing the system.

At this point, the control panel and transmitters are now ready to monitor for the presence of

the target gas(es) and control the ventilation system to efficiently remove the gas from the

protected area.

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Installation

Mounting the Control Panel

The control panel is the central hub for monitoring and controlling all of the transmitters.

However, it does not necessarily need to be mounted in a centralized location. It should be

mounted indoors in a dry location where authorized users will have easy access and the

display can be easily read. Avoid placing the control panel in areas that might need to be

evacuated during a high-gas alarm condition.

The control panel is attached in the mounting position in one of two ways.

•Attach the housing to a four inch conduit box using standard ½” conduit fittings. If you

use this method, make sure that the four inch box is securely attached with screws to a

solid support base. Firmly tighten the threaded nuts on the conduit fittings so they will

not loosen over time.

•Attach the housing to a solid support base using screws through the holes in the

mounting feet.

Find a flat area at least 8 inches wide by inches tall and place the back of the

housing flat against it. Using a pencil or other slender marking tool, mark the location of

the four mounting holes using the housing as a template. Start the screws without the

housing in place to avoid any possibility of damage to the housing. Remove the screws,

place the housing in position, and install the mounting screws. Do not over-tighten the

screws as this may crack the plastic housing.

Mounting the Transmitters

The ability of the transmitters to sense the target gas and efficiently control the ventilation

system depends greatly upon proper selection of the mounting location. A transmitter monitors

the area around it by sampling the air that passes by the sensor. Since the sensor is mounted

inside a housing, air must diffuse through the intake vents and pass by the sensor on its way

out the exhaust vents. Therefore, the transmitter should be positioned where it can sample air

that contains a target gas concentration representative of the average value in that area.

When determining the mounting location, give special consideration to the following guidelines.

•Use one sensor per target gas for each area to be covered.

•Always prioritize locations with the highest occupation density.

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•Do not locate any transmitter further than 4000 feet from a control panel or expansion

pack.

•The types of gases each unit is designed to monitor have densities approximately equal

to that of air. For maximum safety, mount the unit at the average breathing height –

approximately 5 to 7 feet from the floor.

•Avoid mounting locations that would not be representative of the average gas value in

that area. These include but are not limited to locations near doorways, fans, ventilation

inlets and outlets, and areas with air velocities in excess of 3.3 ft/s ( m/s).

•Avoid locations that would allow direct contact with water. Mounting the unit near

outside garage doors may allow rain to hit the unit when the door is open.

•Avoid locations that are directly in the outlet air vents of heaters or air conditioners.

•Avoid mounting locations with normal ambient temperatures below -4°F (-20°C) or

above 22°F (50°C).

•Do not allow exhaust from engines to flow directly on the unit. Each unit is designed to

sense gas concentrations that are 300 to 000 times less concentrated than the gas

levels found in engine exhaust. Also, engine exhaust contains high levels of other

components. These components can shorten the useful life of the sensor if they contact

the sensor before being diluted by the room air volume.

•Avoid mounting locations where the unit may be hit by passing vehicles. If the unit must

be mounted in these locations, provide a shielding cage around the unit for protection.

•Do not restrict the air flow to the unit housing.

•Do not mount the unit in a corner.

•Do not mount the unit near containers of chemicals such as gasoline, kerosene, alcohol,

or other cleaning fluids. High level concentrations of these chemicals may be mistaken

as the target gas by the sensor and cause false readings. Also, some welding gases

may cause false readings.

The transmitter is attached in the mounting position in one of three ways.

•Attach the housing to conduit using appropriate conduit fittings. If you use this method,

make sure that the conduit is securely attached to a solid support. Firmly tighten the

threaded nuts on the conduit fittings inside the transmitter housing so they will not

loosen over time.

•Attach the housing to a four inch square conduit box using the ½ inch fitting provided

with the transmitter. Make sure that the conduit box is firmly fastened to the mounting

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surface with screws. Securely tighten the fitting nut on the inside of the conduit box so it

will not loosen over time.

•Attach the housing to a solid support base using screws through the internal housing

mounting holes. This method requires removal of the housing cover to gain access to

the mounting holes. A mounting hole is located at the top and bottom of each housing

end wall.

Find a flat area at least 6 inches high by 6 inches long and place the back of the open

housing flat against it. Using a pencil or other slender marking tool, mark the location of

the four mounting holes using the housing as a template. Start the screws without the

housing in place to avoid any possibility of damage to the housing or circuit boards.

Remove the screws, place the housing in position, and install the mounting screws. Do

not over-tighten the screws as this may crack the plastic housing. Be careful not to

damage the printed circuit board. Carefully replace the housing cover and securely

tighten all four of the cover retaining screws.

Connecting the Power Suppl

While this control panel does not require much power to operate, it is usually located near

machines that do consume large amounts of power. When these large machines operate, they

cause large voltage spikes to appear on the AC wiring. These spikes can interfere with the

proper operation of the control panel or transmitters. The easiest way to avoid much of this

interference is by providing power to the system through a dedicated circuit from the service

panel. In some very noisy situations, a line filter can be connected in the power supply circuit

just ahead of the wiring connections at the panel.

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WARNING

This detector may require the use of voltage levels high enough to cause fatal injuries.

Proper procedures must be followed any time work is performed on this unit.

Only qualified personnel should attempt to install, maintain, or service this equipment.

Note

Do not operate the detector on the same AC circuit as the ventilation components. Doing

this will almost always cause improper operation.

Provide a dedicated circuit at the required operating voltage at each panel and transmitter

mounting location. Follow all national and local wiring codes. A conductor connected to earth

ground should also be provided. The circuit must include a disconnect switch located within

easy reach of the panel.

Be sure that the step-down transformer provides 24 VAC and has the necessary volt-amp

rating to power each component in the system. Each control panel requires 0.75 VA, each

transmitter requires 2.4 VA, and each expansion pack requires 0.4 VA.

Connect the incoming power conductor to 8-24VAC, the return conductor to 8-24RET, and

the ground conductor to the green screw.

If minor maintenance work needs to be performed on the control panel, there is a power switch

for the panel to the left of the incoming power wires on the printed circuit board. By default,

this switch is in the “OFF” position.

Connecting the Remote Transmitters

The control panel does not supply power to the remote transmitters. However, power may be

daisy chained through the control panel to the transmitters. Use a two-conductor cable with

color-coded conductors of at least 8 AWG to connect the power. Use a shielded, twisted-pair

cable with color-coded conductors of at least 24 AWG to connect communication. A single

four-conductor cable may be used but will reduce the maximum distance the system can

cover. See figure 0 on page 53 and figures 6 and 7 on page 57 for details. If possible,

choose cables with color-coded conductors that follow the suggested color scheme listed on

the drawings.

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CAUTION

Operating these devices with the incorrect voltage and power requirement can cause

internal electrical components to overheat and fail. Operation with the wrong power

requirements will void the manufacturer’s warranty, and the installer will be responsible for

any damage that occurs.

Contact Brasch Environmental Technologies, LLC before connecting power to the control

panel and transmitters if you are unsure of the correct power requirement.