Munters Rotem RBU-27 SE Guide

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Table of Content
1. Front matter ............................................................................................................................................ 4
1.1 Introduction.....................................................................................................................................4
1.2 Conventions....................................................................................................................................4
1.3 Contact Information......................................................................................................................... 4
1.4 Document Information..................................................................................................................... 4
2. Precautions............................................................................................................................................. 5
3. Introduction to the RBU-27 SE............................................................................................................... 5
3.1 Switch Functions............................................................................................................................. 6
3.2 RBU-27 SE Functions..................................................................................................................... 7
3.2.1 Inlet or Tunnel Air Source...................................................................................................... 7
3.2.2 Cool Weather Protection........................................................................................................ 7
3.2.3 Hot Weather Protection ......................................................................................................... 8
3.2.4 Platinum Fail Safe ................................................................................................................. 9
3.2.5 Inlet/Tunnel Power Supply..................................................................................................... 9
4. Specifications....................................................................................................................................... 10
5. Installation............................................................................................................................................. 11
5.1 Safety Instructions......................................................................................................................... 11
5.2 Mounting the Unit.......................................................................................................................... 11
5.3 sPlatinum Controller Notes............................................................................................................ 11
5.4 Wiring ........................................................................................................................................... 11
5.5 Drilling........................................................................................................................................... 18
6. Troubleshooting ................................................................................................................................... 19
6.1 General Issues.............................................................................................................................. 19
6.2 Contactors and Terminals Issues.................................................................................................. 19
6.2.1 Contactor Check and Terminals Example............................................................................ 19
6.2.2 Internal Contacts................................................................................................................. 20
7. Appendix A: Adding a Timer Stage ..................................................................................................... 23
8. Appendix B: Electrical Grounding....................................................................................................... 25
8.1 Ground Rods................................................................................................................................. 25
8.2 Ground Wire.................................................................................................................................. 25
8.3 Ground Clamps............................................................................................................................. 25
8.4 What Should Be Grounded?.......................................................................................................... 26
9. Warranty & Limitation of Liability........................................................................................................ 27

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1. Front Matter
This section includes general information on the document and the company.
1.1 Introduction
Rotem manuals provide easy-to-use information regarding the installation, operation, long/short term planning and parts
listing (this manual may not deal with all of the above subjects). The table of contents is an outline of the relevant
information in this manual.
Read this manual before operating your Rotem product. Using this equipment for any other purpose or in a way not within
the operating recommendations specified in this manual voids the warranty and may cause personal injury. If you have
any questions or comments regarding your product, please contact your local Rotem dealer.
1.2 Conventions
NOTE: Notes provide important details regarding specific procedures.
CAUTION: Cautions alert you to potential damage to the controller if the procedures are not followed carefully.
WARNING! Warnings alert you to potentially hazardous situations which, if not avoided could result in
death or personal injury.
This symbol means that certain hardware must be installed or functions defined before a screen can be used.
1.3 Contact Information
Email: s[email protected] Website: http://www.rotem.com
1.4 Document Information
Revision History
Revision Level / Date
Section Affected
Description
1.0 / Jan 2016
Release document
1.1 / Feb 2016 5.4 Wiring diagrams
1.2 / May 2016
3.2.1
Added description and warning
1.3 / July 2016
5, 8
Updated wiring diagrams
1.4 / Dec 2016 3.2.3/3.2.4 Updated timer info
1.5 / May 2017
New format
© 2011 Rotem Corp. All rights reserved. Document Number: 110557
No part of this publication may be reproduced, stored in an automated data file or made public in any form or by any
means, whether electronic, mechanical, by photocopying, recording or in any other manner without prior written
permission of the publisher. Rotem will not accept responsibility for damage resulting from the use of this manual. Rotem
also reserves the right to make changes and improvements to its products and/or the associated documentation without
prior notice.
Software Version: N/A Document Version: 1.5

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2. Precautions
•Ensure that the unit is grounded as explained in Appendix B: Electrical Grounding, page 18.
•It is extremely important that the Inlet/Tunnel switch be set correctly! Failure to do so can cause major damage to your
flock/herd or physical plant. Refer to Inlet or Tunnel Air Source, page 7.
3. Introduction to the RBU-27 SE
The RBU-27 SE system is a backup controller that operates during a primary controller failure or during extreme
temperatures. The RBU-27 SE has 27 heavy duty relays, up to five thermostats and four delay times. The RBU-27 SE is
a five stage backup consisting of:
oone heating stage having two heat zones
othree cooling stages
oone cool pad stage
•up to four cool pad pumps
•temperature independent
Each stage is powered from its own circuit breaker. LED indicators on the front panel indicate which stages are currently
active.
oTo prevent overheating, all four heater relays are defined as Off or Auto.
oTo ensure cooling in all situations, all 16 cooler relays are defined as On or Auto (two fans can be set to On,
Off, or Auto).
The RBU-27 SE can be expanded to include up to four heaters, four cool pads, and 16 fans. The unique design provides
a greater control in choosing the ventilation method, testing equipment, and emergency climate control (Latch On/Off
function).
Figure 1 shows a pre-wired relay; the relay’s logic serves as the RBU-27 SE’s “non-electronic brain”. In addition, the relay
is highly resistant to lightening and other transient electrical disturbances.
Figure 1: Pre-Wired Relays
NOTE: While the RBU-27 SE is designed to work with Rotem’s Platinum Controllers, it supports all Rotem Controllers.
oSwitch Functions
oRBU-27 SE Functions

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3.1 Switch Functions
Figure 2 illustrates the front panel and Table 1 lists the available switch functions.
Figure 2: Controller Front Panel
LED
When On
Controller Alarm
Indicates controller failure
Heat Stage
Heat stage is active
Cool Pad Stage Cool pad stage is active
Cool Stage 1/2/3
Cool stage is active
Table 1: Available Switch Functions
Switch
Function
Comments
Inlet/Tunnel
Toggles between ventilation methods:
•Inlet: One or two vents open.
•Tunnel: Tunnel curtain opens in case of backup
operation
Ventilation method depends on the livestock
age, the equipment in the house, and the
season of the year. Important: Refer to Inlet or
Tunnel Air Source, page 7.
Latch On/Off
•Latch ON: Once Thermostat 4 (Cool Stage 2) is
activated, the RBU continues to run in Cool Stage
2 (Fans 1-10) until switched off manually.
•Latch OFF: RBU runs Cool/Heat Stages
according to thermostats.
You can use the Latch feature to lock the
facility into tunnel mode for an extended period.
This may help remove built up heat stress in
your poultry.

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Switch
Function
Comments
Heater 1 – 4
Off/Auto
The Off option prevents heater activity. The Auto
option activates heaters only if the thermostat
temperature set point has been reached.
Each stage has its own circuit breaker, and its
own thermostat.
Cool Pad 1 –
4
The On option activates the sprayers manually. The
Auto option activates the sprayers according to
temperature readings of the thermostat.
Fans 1 – 2 / 5
- 16
The On option activates the fans manually. The Auto
option activates the fans according to temperature
readings of the thermostat.
Each stage has its own circuit breaker, and its
own thermostat.
Fans 3 - 4
The On option activates the fans manually. The Off
option prevents the fans from operating. The Auto
option activates the fans according to temperature
readings of the thermostat.
Each stage has its own circuit breaker, and its
own thermostat.
3.2 RBU-27 SE Functions
The RBU-27 SE has the following functions:
oInlet or Tunnel Air Source
oCool Weather Protection
oHot Weather Protection
oPlatinum Fail Safe
oInlet/Tunnel Power Supply
3.2.1 Inlet or Tunnel Air Source
The following section details how the RBU-27 SE operates the house's air sources.
oActive Cool Stage
oAir Source Setting
3.2.1.1 Active Cool Stage
RBU-27 SE controls two sources of the chicken/pig house air supply, inlets and tunnels. In general, inlets are used during
the winter to supply minimum ventilation. Tunnels are used in the summer when the required air supply increases to the
point where minimum ventilation is insufficient.
oWhen Cool Stage 1 or 2 is active, the toggle switch position defines the air source (inlet or tunnel).
oWhen Cool Stage 3 is active, the air source is the tunnel ventilation only. If the Inlet/Tunnel toggle switch is
set to Inlet, RBU-27 SE bypasses the setting.
3.2.1.2 Air Source Setting
It is extremely important to ensure that the RBU-27 SE air source is set correctly.
oUsing tunnel ventilation in the winter can bring in too much cold air, endangering your birds/animals health.
oInlets supply only a limited supply of air. The house's fans remove the house's air, creating negative
pressure. When Cool Stage 2 begins, Fan 5 – 10 begin to operate (along with Fans 1 – 4). In this situation,
negative pressure can drop so low that the drop ceiling can physically collapse.
WARNING! It is extremely important that the Inlet/Tunnel switch be set correctly! Failure to do so can
cause major damage to your flock/herd or physical plant.
3.2.2 Cool Weather Protection
If the temperature drops to the specified levels, RBU-27 SE’s heaters begin to function. Thermostat 1 controls Heaters 1-
4 and Thermostat 2 controls Heaters 5 - 8.
NOTE: If the heaters are installed in different locations (heat areas) they function independently.

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3.2.3 Hot Weather Protection
oStage operation:
•If the house temperature rises to Thermostat 3’s set temperature, the RBU-27 SE launches Cooling
Stage 1 and operates Fans 1-2 and 3-4 to lower temperatures.
•If temperature continues to rise to Thermostat 4’s set temperature, the RBU-27 SE launches Cooling Stage
2 (Fans 5-6, 7-8, and 9-10) and uses the Inlet or Tunnel option as well.
•If the temperature continues to rise to Thermostat’s 5 set temperature, Cooling Stage 3 (Fans 11-12, 13-14,
and 15-16) launches.
•If Thermostat 4’s set temperature is lower than Thermostat 3’s set temperature, Cooling Stage 1 begins
simultaneously with Cooling Stage 2.
oInlet or Tunnel option: The inlets/tunnels open when the first cooling stage begins. In practice, this means
the inlets/tunnels open when Cooling Stage 1 begins.
•If Thermostats 3 and 4's set temperature are higher than Thermostat 5's, the inlet/tunnel opens when
Cooling Stage 3 begins.
•If Thermostats 3's set temperature is higher than Thermostat 4 and 5's, the inlet/tunnel opens when
Cooling Stage 2 begins.
Table 2 lists the cooling stages activation and timer delays.
Table 2: Cooling Device Settings
Cool Stage
Thermostat
Active Devices
Default Timer Delay
1 3 Fans 1-4 and Inlet or Tunnel Curtains 60 seconds
2
4
Fans 1-4 / 5-10 and Inlet or Tunnel Curtains
90 seconds
3
5
Fans 1-10 / 12-16 and Inlet or Tunnel Curtains
120 seconds
N/A Fail safe delay 30 seconds
Cool pad
2
Cool pads 1-4
N/A
NOTE: Rotem recommends using the default timer delays; however the timer can be adjusted to any time setting on
the potentiometer.
NOTE: Timer delay differs if when the unit is in Fail Safe mode. Refer to Platinum Fail Safe.
To adjust the delay:
1. Disconnect power from the RBU-27 SE.
2. Open the unit.
3. Adjust the timer delay potentiometers as required (Figure 3).
4. Figure 4 illustrates which potentiometer controls the delay for the different stages.
Figure 3: Timer Delay Unit

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3.2.4 Platinum Fail Safe
In case of a failure in a Platinum controller, the RBU-27 SE:
oopens the selected air source (Inlet or Tunnel)
oturns on Fans 1-4
olights the Controller Alarm LED
NOTE: Only Platinum Controllers support the Fail Safe feature.
WARNING! On the Platinum Front Panel, set the Fail Safe Relay to Auto. Do not set the Fail Safe relay
switch to ON. Setting the switch to On overrides the software; the relay is not released during
a controller failure and RBU-27 SE does not operate!
Set a relay in the Platinum Controller to act as the fail-safe relay.
oTimer Delay
oSetting the Relay
3.2.4.1 Timer Delay
Normally, RBU-27 SE timers operate consecutively. Meaning, each device's begins to operate 1) only after the previous
device is already operating and 2) after the device's delay time has elapsed. However, in Fail Safe mode all devices begin
to operate simultaneously, after the 30 second delay time has passed.
3.2.4.2 Setting the Relay
Platinum Software Version 3.0 and above includes a dedicated Fail Safe relay.
Go to Management> Fail Safe settings and configure the alarm type for the fail safe function.
3.2.5 Inlet/Tunnel Power Supply
Even during normal operations, power to the Platinum Controller Open Inlet/Tunnel is routed through the RBU-27 SE.
When the RBU-27 SE takes control for opening the inlets or tunnel curtains, it disconnects power to the Platinum.
NOTE: The RBU-27 SE only opens inlets or tunnel curtains. It does not close them.
Anytime that the RBU-27 SE detects that power is not being supplied via L1 it automatically activates Fans 1 – 4. In this
case, the Control Failure LED is lit on the front panel.

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4. Specifications
Power Supply
Mains voltage
Single phase 115 VAC 50 - 60 Hz
Mains frequency
50/60 Hz
Relays Outputs
Resistive load
30 A, 277 VAC
Housing
Polycarbonate
UL 94-5V IP 65
Dimensions (L x W x H)
500 x 400 x 200 mm (19.7 x 15.7 x 7.9 inches)
Ambient Climate
Operating temperature range
0°to +50°C / (22°to 125°F)
Storage temperature range
-10°to +70°C / (14°to 158°F)
Operating humidity range
0 to 100%
Environmental Protection
Recycle raw materials instead of disposing as waste. The controller, accessories and packaging
should be sorted for environmental-friendly recycling. The plastic components are labeled for
categorized recycling.

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5. Installation
The following sections describe the installation process.
•Safety Instructions
•Mounting the Unit
•Platinum Controller Notes
•Wiring
•Drilling
5.1 Safety Instructions
To protect yourself and your controller, observe the following rules:
•ONLY an authorized electrician may install the RBU-27 SE.
•Disconnect the power to avoid electrical shock and damage.
•Install the RBU-27 SE in the service room to avoid exposing the unit to harmful gases or high humidity.
•Always disconnect the power before opening the front enclosure door.
WARNING! There is a risk of an electric shock when working with the unit.
CAUTION: Any use of the RBU-27 SE in way which is not specified by Rotem may impair the equipment
protection.
5.2 Mounting the Unit
1. Connect the equipment according to the tags written on the PCB. Figure 4 displays some of the connections.
2. Connect the heater to Relays K24 and K25, fans to Relays K16 through K23, and cool pads to K26 and K27.
Figure 14 displays the relay numbers. See Figure 5.
3. Make proper grounding connections.
4. Set the thermostats to the required temperatures and the timers to the required delay time.
5. Perform a primary controller failure to make sure the backup system functions.
6. Verify that the fans and heaters are working by moving switches to "ON" position.
7. Lower thermostats temperature set points and ensure they are functioning properly. Toggle between Inlet and
Tunnelto see that they are also properly connected.
8. Toggle between Latch On/Off while the backup is active and turn the controller on and off to make sure everything
is connected properly.
NOTE: If the RBU-27 SE is set to Latch On, the backup continues to function as the primary controller even after the
controller starts working.
5.3 Platinum Controller Notes
1. To power the Platinum Controller, apply 220 volts AC (single phase) to a Platinum power connector, and connect a
safety ground to the Ground Bus.
2. In the RBU, connect Neutral to the 1st terminal.
3. Connect L1 for Inlet and Tunnel Machines from their circuit breakers to the corresponding terminal in the RBU. The
backup turns L1 back out on the PWR pin immediately to the right of L1 inputs.
4. Connect the PWR pin to the corresponding relays in the Platinum Controller Electrical Grounding for Controllers.
5.4 Wiring
oFigure 5: Relay Connections to Controller – Section 3
oFigure 6: Vent Machine Wiring
oFigure 7: Fan and Cooling Wiring

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oFigure 8: Heater Wiring
oFigure 9: Fail Safe Wiring
oFigure 10: Relays Diagram – Inlet / Tunnel – Section 3
Figure 4: Card View
Figure 4 presents a view of the card divided into the following main sub-units:
oSection 1 - Pre-wired sub-units: Designed to be used only in case an error occurs. Only authorized
technicians can replace or repair these subunits.
oSection 2 - Fans and heater contacts: Designed to define the relays that active the cool pad, fans, and the
heaters. Figure 6, Figure 7, and Figure 8 focus on defining the connections to the controller and other
equipment.
oSection 3 - Thermostat and vents connection sub-unit: Illustrated in Figure 10. Designed to connect the
Tunnel curtain and the Inlet.
Note that each cool pad, fan, and heater has a separate pair of relay contacts capable of directly driving the load. The
board connections are written on the board in the following order (left to right):

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oNeutral
oInlet Line (L1)
oPower to Inlet
oOpen1 and Open2
oTunnel Line (L1)
oPower to Tunnel
oTunnel Open
oHeat Line
oThermostat common (TC)
oThermostat normally closed (TNC)
A similar order applies for other heaters and fans.
During normal operation the Platinum Inlet/Tunnel curtain is connected through the RBU-27 SE PWR output (L1). In case
of a Platinum failure or in case the RBU-27 SE thermostat reaches the set point (Main Controller failure), the RBU-27 SE
takes control and cuts the PWR output to the Platinum and opens Inlet/Tunnel curtain. This feature prevents conflicting
commands between RBU-27 SE and Platinum.
NOTE: Other powered devices (for example heaters or fans) are powered normally.
Figure 5: Relay Connections to Controller – Section 3
NOTE: The following drawings illustrate installation examples. In an actual installation the relays used can differ.

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Figure 6: Vent Machine Wiring
Notes:
•During normal operation, the RBU-27 SE connects L1 through PWR to the Platinum relays. During emergencies, the
RBU stops supplying power to the Platinum controller.
•The RBU-27 SE can only open the vent machines.
•If the vent machines operate backwards, swap the L1 and L2 wires at the Platinum relays or at the vent machine.
•Do not change the wiring on the vent machine left terminal.

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CAUTION: Connect a safety ground and follow the National Electrical Code!
Figure 7: Fan and Cooling Wiring
Notes:
•The fans connect in standard order (meaning factory labeled) in the RBU-27 SE.
•Cool 1 (Platinum Relay) and Cool 2 (Platinum Relay) connect from the Platinum Extension Box to Fan 15 and Fan 16
terminals in the RBU-27 SE.
•Avoid using 120 volt motors (Cool 1 and 2) if possible. They stress Platinum relays more than 240 volt motors. If you
do use 120 volt motors, derate from 2 HP UL about 50%.

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Figure 8: Heater Wiring
Notes:
•Connect L1 Power to the RBU-27 SE from the Heater 1 circuit breaker (not shown in diagram).
•Back up heaters in the brooding zone (up to 4).
•Backup turns heaters on in one zone (one thermostat).
Figure 9: Fail Safe Wiring

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Figure 10: Relays Diagram – Inlet / Tunnel – Section 3

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5.5 Drilling
Drill several holes on the bottom of the unit. Route the cables through these holes/
Figure 11: Hole locations (example)
NOTE: Figure 11 is an example only. The number of holes in each installation depends on the number of cables
being run.

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6. Troubleshooting
The following sections detail how to troubleshoot the RBU-27 SE.
oGeneral Issues
oContactors and Terminals Issues
6.1 General Issues
Table 3 describes the outputs and their related relays. In case there is a problem check the following before
troubleshooting your unit:
oVoltage
oCircuit breakers
oAll other connections
After verifying that the above are operating, follow the instructions given in Table 3 .
Table 3: General Troubleshooting Issues
Issue #
Issue Description
Related Relay
1
Inlet open1 power fails
Replace K2
2
Inlet open2 fails
Replace K3
3 Tunnel open power fails Replace K5
4
Fan 1 & 2 fails
Replace K16
5
Fan 3 & 4 fails
Replace K17
6
Fan 5 & 6 fails
Replace K18
7
Fan 7 & 8 fails
Replace K19
8 Fan 9 & 10 fails Replace K20
9
Fan 11 & 12 fails
Replace K21
10
Fan 13 & 14 fails
Replace K22
11
Fan 15 & 16 fails
Replace K23
12
Heater 1 & 2 fails
Replace K24
13 Heater 3 & 4 fails Replace K25
14
Cool Pad 1 & 2 fails
Replace K26
15
Cool Pad 3 & 4 fails
Replace K27
6.2 Contactors and Terminals Issues
Table 4, Table 5, and Table 6 detail troubleshooting issues that concern contactors and terminals. For layout issues, refer
to Figure 14.
6.2.1 Contactor Check and Terminals Example
To check K4, ensure that the inputs/terminals settings are set as follows:
TH1: short
TH2:
open
TH3:
open
TH4:
open
TH5:
open
PP-F:
short
Latch:
off

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Figure 12: Shorting the unit
6.2.2 Internal Contacts
To check internal contacts:
1. With the power off, disconnect the quick connect from the COM, NO and NC relay terminals (Figure 13).
2. Turn the power back on.
3. Using an Ohm meter, check that the resistance between the COM and NO is zero (0), and the contact between
COM and NC is open.
4. Turn the power OFF, and check that the contact between the COM and NO is open, and check that the resistance
between COM and NC is zero (0).
5. Reconnect the quick connect to COM, NO and NC relay terminals and turn the power back on.
Figure 13: Testing internal contacts
Table 4: Detailed Troubleshooting Issues I
Contactors K1-10
K1 K2 K3 K4 K5 K6 K7 K8 K9 K10
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V
115V 115V 115V
Inputs/Terminals
Inlet, All Switches-Auto
TH1
TH2
TH3
TH4
TH5
PP-F
Latch
short
open
open
open
open
short
off
open
short
open
open
open
short
off
open
open
open
open
short
short
off
open
open
open
open
open
open
off
open
open
open
short
open
short
off