Lenze AC Tech MCH Series Use and care manual

MCH Series Drives
BACnet Communications Guide

This documentation applies to the use of an MCH Series Variable Frequency Drive with BACnet protocol and should
be used in conjunction with the MCH Series Installation and Operation Manual (Document MH01) that shipped with
the drive. These documents should be read in their entirety as they contain important technical data and describe
the installation and operation of the drive.
ASHRAE and BACnet® are registered trademarks of the American Society of Heating, Refrigerating and Air-
Conditioning Engineers, Inc., 1791 Tullie Circle NE, Atlanta, GA 30329, http://www.bacnet.org.
Modbus ™ is a registered trademark of Schneider Electric, founder of Modbus-IDA, http://www.modbus-IDA.org.
© 2003 AC Technology Corporation
No part of this documentation may be copied or made available to third parties without the explicit written approval
of AC Technology Corporation. All information given in this documentation has been carefully selected and tested
for compliance with the hardware and software described. Nevertheless, discrepancies cannot be ruled out. AC
Tech does not accept any responsibility nor liability for damages that may occur. Any necessary corrections will be
implemented in subsequent editions.
About These Instructions

i RG-MHBAC
Contents
1 Safety Information.............................................................................................................1
1.1 Warnings, Cautions and Notes ..............................................................................1
1.1.1 General ....................................................................................................1
1.1.2 Application ...............................................................................................1
1.1.3 Installation ...............................................................................................1
1.1.4 Electrical Connection................................................................................2
1.1.5 Operation .................................................................................................2
2 Introduction.......................................................................................................................3
2.1 MS/TP Communications........................................................................................3
2.2 MS/TP Physical Layer ...........................................................................................3
2.3 Serial Communications Wiring ..............................................................................3
3 Drive Setup and Programming...........................................................................................4
3.1 Added Programming Parameters ..........................................................................4
3.2 Omitted Parameters and Selections ......................................................................4
3.3 Modified Parameters and Selections .....................................................................5
3.4 Serial Communication Setup.................................................................................5
4 MCH BACnet® Objects......................................................................................................8
4.1 BACnet® Object Map............................................................................................8
4.2 Analog Input (AI) Object Descriptions.....................................................................9
4.3 Analog Value (AV) Object Descriptions...................................................................9
4.4 Binary Input (BI) Object Descriptions .....................................................................10
4.5 Binary Output (BO) Object Descriptions .................................................................10
4.6 Binary Value (BV) Object Descriptions ...................................................................10
4.7 Multi-State Input (MSI) Object Descriptions ...........................................................11
4.8 Multi-State Value (MSV) Object Descriptions .........................................................13
4.9 Reference and Links .............................................................................................13

1 RG-MHBAC
Safety Information
1 Safety Information
1.1 Warnings, Cautions and Notes
1.1.1 General
Some parts of Lenze controllers (frequency inverters, servo inverters, DC controllers) can be live, moving
and rotating. Some surfaces can be hot.
Non-authorized removal of the required cover, inappropriate use, and incorrect installation or operation
creates the risk of severe injury to personnel or damage to equipment.
All operations concerning transport, installation, and commissioning as well as maintenance must be
carried out by qualified, skilled personnel (IEC 364 and CENELEC HD 384 or DIN VDE 0100 and IEC report
664 or DIN VDE0110 and national regulations for the prevention of accidents must be observed).
According to this basic safety information, qualified skilled personnel are persons who are familiar with
the installation, assembly, commissioning, and operation of the product and who have the qualifications
necessary for their occupation.
1.1.2 Application
Drive controllers are components designed for installation in electrical systems or machinery. They are
not to be used as appliances. They are intended exclusively for professional and commercial purposes
according to EN 61000-3-2. The documentation includes information on compliance with EN 61000-3-2.
When installing the drive controllers in machines, commissioning (i.e. the starting of operation as directed)
is prohibited until it is proven that the machine complies with the regulations of the EC Directive 98/37/EC
(Machinery Directive); EN 60204 must be observed.
Commissioning (i.e. starting drive as directed) is only allowed when there is compliance to the EMC Directive
(89/336/EEC).
The drive controllers meet the requirements of the Low Voltage Directive 73/23/EEC. The harmonised
standards of the series EN 50178/DIN VDE 0160 apply to the controllers.
The availability of controllers is restricted according to EN 61800-3. These products can cause
radio interference in residential areas. In the case of radio interference, special measures may be
necessary for drive controllers.
1.1.3 Installation
Ensure proper handling and avoid excessive mechanical stress. Do not bend any components and do not
change any insulation distances during transport or handling. Do not touch any electronic components
and contacts. Controllers contain electrostatically sensitive components, which can easily be damaged by
inappropriate handling. Do not damage or destroy any electrical components since this might endanger
your health! When installing the drive ensure optimal airflow by observing all clearance distances in the
drive's user manual. Do not expose the drive to excessive: vibration, temperature, humidity, sunlight, dust,
pollutants, corrosive chemicals or other hazardous environments.

RG-MHBAC 2
Safety Information
1.1.4 Electrical Connection
When working on live drive controllers, applicable national regulations for the prevention of accidents (e.g.
VBG 4) must be observed.
The electrical installation must be carried out in accordance with the appropriate regulations (e.g.
cable cross-sections, fuses, PE connection). Additional information can be obtained from the regulatory
documentation.
The regulatory documentation contains information about installation in compliance with EMC (shielding,
grounding, filters and cables). These notes must also be observed for CE-marked controllers.
The manufacturer of the system or machine is responsible for compliance with the required limit values
demanded by EMC legislation.
1.1.5 Operation
Systems including controllers must be equipped with additional monitoring and protection devices according
to the corresponding standards (e.g. technical equipment, regulations for prevention of accidents, etc.).
You are allowed to adapt the controller to your application as described in the documentation.
DANGER!
• After the controller has been disconnected from the supply voltage, do not touch the live
components and power connection until the capacitors have discharged. Please observe the
corresponding notes on the controller.
• Do not continuously cycle input power to the controller more than once every three minutes.
• Close all protective covers and doors during operation.
WARNING!
Network control permits automatic starting and stopping of the inverter drive. The system design
must incorporate adequate protection to prevent personnel from accessing moving equipment
while power is applied to the drive system.
Table 1: Pictographs used in these instructions
Pictograph Signal word Meaning Consequences if ignored
DANGER! Warning of Hazardous Electrical
Voltage.
Reference to an imminent danger that may
result in death or serious personal injury if the
corresponding measures are not taken.
WARNING! Impending or possible danger
for persons
Death or injury
STOP! Possible damage to equipment Damage to drive system or its surroundings
NOTE Useful tip: If observed, it will
make using the drive easier

3 RG-MHBAC
Introduction
2 Introduction
This document will explain how to operate an MCH Drive using BACnet protocol on a Master-Slave/Token-
Passing (MS/TP) LAN. It is intended as a serial communications supplement only and will not discuss
normal drive operations. For more information regarding normal drive setup and functionality, refer to the
MCH Installation and Operation Manual (MH01). Some of the information contained in this document was
provided by the ANSI/ASHRAE 135-2001 standard. Refer to http://www.bacnet.org for more information.
2.1 MS/TP Communications
MS/TP communication is maintained by a Master & Slave relationship between the devices on the LAN.
All communication is initiated by Master devices. The token passes network mastership from one Master
device to another. Slave devices never initiate a service request. They only respond to service requests
from master devices. The Native BACnet implementation in MCH Drives is for an MS/TP Slave device.
Therefore, only devices that support static device binding will be able to communicate with an MCH drive.
For an MS/TP EIA-485 network use shielded, twisted-pair cable with a characteristic impedance between
100 and 130 ohms. Maximum recommended length of an MS/TP segment is 1200 meters (4000 feet)
with AWG 18 cable. Maximum number of nodes (unit loads) per segment is 32 (as specified by the EIA-
485 standard). Because MS/TP uses non-return to zero (NRZ) encoding, the polarity of the connection to
the cable is important. The non-inverting input of the EIA-485 transceiver is designated as “+” and the
inverting input as “-”. Connect a termination resistance of 120 ohms (± 5%) at each of the two ends of the
segment medium. Ground the shield at one end only to prevent ground currents from being created. Each
MCH drive is equipped with 100k ohm local bias resistors.
2.2 MS/TP Physical Layer
Communication is half duplex. Bytes are transmitted using NRZ encoding with 1 start bit, 8 data bits, no parity
and 1 stop bit. All bytes are transmitted with the least significant bit first. Communication is asynchronous
with no more than 20 bit times of idle time between any two bytes of a frame. The communication baud
rate for MCH Series Drives is 9600 bps. The bit sequence is as follows:
DATA
START 1 2 3 4 5 6 7 8 STOP
2.3 Serial Communications Wiring
Figure 1 illustrates the MCH Series Terminal Strip and connections for an MS/TP LAN.
21 5A 5B 6 10A 10B 2 13A12A 13B 13C 13D 14 15 2 TXBRXA 16 17 18
EIA-485 -
EIA-485 +
Earth
Ground
Figure 1: MCH Terminal Strip
Connect EIA-485+ terminal to MCH terminal TXB Connect EIA-485- terminal to MCH terminal RXA
Connect MCH terminal 2 to Earth Ground.

RG-MHBAC 4
Drive Setup & Programming
3 Drive Setup and Programming
Most drive parameters (including those required for serial communications) are not accessible through the
LAN. They can only be accessed by entering the Programming Mode of the drive itself. Refer to the MCH
Installation and Operation Manual (MH01) for more information. The parameter information in manual MH01
is based on the standard MCH Series Modbus™ Drive. The differences between the drive programming
parameters described in the manual and those that exist in the MCH Series BACnet® Drive are explained
in sections 3.1-3.3 herein.
3.1 Added Programming Parameters
60 SERIAL TIMEOUT This parameter makes the serial watchdog timeout period selectable. (Section 3.4)
85 DEVICE NUM EX This parameter is used to extend the device number to its full 22-bit range of
0 to 4194303. If the device number of the drive exceeds a value of 65535, this
parameter should be set to the value of bits 16-22 of the device number. Otherwise
this parameter should be set to 0.
86 DEVICE NUMBER This parameter holds the value of bits 0-15 of the drive’s 22-bit device number. It
can be used by itself to represent a device number in the range of 0 to 65535. If the
device number exceeds 65535, then DEVICE NUM EX must also be used.
Example: The device number is 124 (00007Ch). The value of bits 16-22 (DEVICE NUM EX) is
00h or 0. The value of bits 0-15 (DEVICE NUMBER) is 007Ch or 124.
Example: The device number is set to its default value of 1240000 (12EBC0h). The value of
bits 16-22 (DEVICE NUM EX) is 12h or 18. The value of bits 0-15 (DEVICE NUMBER)
is EBC0h or 60352.
NOTE
The values of the DEVICE NUMBER and DEVICE NUM EX parameters are also appended to the
object name of the drive to ensure that it is unique network-wide.
Example: If the device number of the drive is set to its default value of 1240000 (12EBC0h),
the resulting object name for the device will be ‘AC Tech VFD 18-60352’.
3.2 Omitted Parameters and Selections
36 SLEEP THRESHOLD Sleep Mode functionality has not been added to the MCH Series BACnet®
drive so these drive parameters do not exist.
37 SLEEP DELAY
38 SLEEP BANDWIDTH
41 ANALOG INPUT FILTER
52 TB14 OUT The following options have not been added to these parameters in the MCH
Series BACnet® drive:
53 TB15 OUT
54 RELAY INV MIN/MAX A
MIN ALARM
INV MIN ALARM
MAX ALARM
INV MAX ALARM

5 RG-MHBAC
Drive Setup & Programming
3.3 Modified Parameters and Selections
24 AUTO SOURCE The default selection for this parameter has been changed to KEYPAD. Refer to
Section 3.4 Serial Communications Setup for more information.
32 HZ MULTIPLIER The default setting for this parameter has been changed to 30.00. Refer to Section
3.4 Serial Communications Setup for more information.
56 SERIAL LOSS The selections for this parameter are FAULT (default) and PRESET#3. The functionality
of this parameter is described in detail in Section 3.4 Serial Communications Setup.
57 SERIAL The default selection for this parameter has been changed to WITH TIMER to provide
limited “out-of-thebox” serial communication with the drive.
58 MAC ADDRESS This parameter has been renamed to be consistent with BACnet nomenclature. The
minimum and maximum values for this parameter have also been changed to 0
and 254, respectively, in accordance with ANSI/ ASHRAE Standard 135-2001. The
default value is 128. Refer to Section 3.4 for more information.
3.4 Serial Communication Setup
The factory default values of the drive parameters have been set to allow the monitoring of all MCH BACnet
points. Write commands will not be accepted without proper modification to these drive settings. One
exception to this is STOP commands, which are always accepted over the LAN. For serial start and/or serial
speed and setpoint control, modify the setting of Drive Parameter #30 (Control). The drive parameters that
are required for serial communications, including Drive Parameter #30, are described herein.
24 AUTO SOURCE This parameter must be set to KEYPAD for the drive speed or setpoint to be modified
over the LAN.
30 CONTROL This parameter should be set to accommodate the specific application intent:
NORMAL Serial start and serial speed/setpoint commands are invalid.
NORM NO HAND Same as NORMAL except the HAND/OFF/AUTO, herein referred to
as H/O/A, is limited to settings of OFF and AUTO.
SERIAL SPEED Serial start commands are invalid. Serial speed/setpoint
commands are valid in AUTO H/O/A.
S SPD/NO HAND Same as SERIAL SPEED except H/O/A is limited to settings of OFF
and AUTO.
SERIAL AUTO Serial start and serial speed/setpoint commands are all valid in
AUTO H/O/A. This setting forces the drive to be started over the
LAN when in AUTO H/O/A.
S AUTO/NO HND Same as SERIAL AUTO except H/O/A is limited to settings of OFF
and AUTO.
Serial STOP commands are accepted over the LAN regardless of this parameter setting.

RG-MHBAC 6
Drive Setup & Programming
NOTE
• Drive Parameter #30 (CONTROL) must be set to SERIAL AUTO or S AUTO/NO HND in order
to start the drive over the LAN.
• The upper left corner of the drive display must indicate SSTOP for a serial start command
to be accepted by the drive.
• If the display reads KSTOP (keypad stop) then the AUTO START or HAND START button
must be pressed to clear the keypad stop condition.
• If the display reads RSTOP (remote terminal stop) then there is an open external contact
that needs to be closed.
• If the drive is a standalone drive or has an option box, make sure that the TB1-to-
TB2 contact is being made.
• If the drive has a bypass, make sure that the drive is in AUTO H/O/A and that all
of the safety and customer start contacts are closed (specifically the B3-to-B4
contact which is not made when the drive leaves the factory).
56 SERIAL LOSS This parameter sets the action to be taken in the event that the Drive Parameter #30
(Control) is set to SERIAL SPEED and the LAN had modified the speed or setpoint
command prior to a serial watchdog timeout occurrence. The options for this
parameter are FAULT (default) and PRESET#3.
If FAULT is selected and the drive is running when a serial watchdog timeout occurs
the drive will trip into a SERIAL FAULT stopping the drive and taking it out of serial
control. A fault reset command (issued via the Clear Fault point), a keypad stop or a
terminal stop is required to clear the fault. A stop command from the LAN will also
clear the fault if it is the highest priority command in the priority array.
If PRESET#3 is selected, Drive Parameter #30 (Control) is set to SERIAL SPEED and
the drive is running when a timeout occurs, the drive will continue to run but will get
its speed command from Drive Parameter #3 (PRESET #3). If the drive is stopped
(KSTOP, RSTOP, SSTOP or FAULT), placed in HAND or OFF or serial communications
are restored, the drive will return to its normal speed/setpoint reference.
When Drive Parameter #30 (Control) is set to SERIAL SPEED, the speed reference
MUST be the drive keypad (-KEY, -MKB, -AKB or -SER) for the serial loss action to
take effect.
If Drive Parameter #30 (Control) is set to SERIAL AUTO the serial loss action is ignored
and the drive trips into a SERIAL FAULT stopping the drive and taking it out of serial
control.

7 RG-MHBAC
Drive Setup & Programming
57 SERIAL This parameter needs to be set to either WITH TIMER (default) or W/O TIMER for
the drive to communicate with the LAN. Serial communications will not work if this
parameter is set to DISABLED.
58 MAC ADDRESS This parameter contains the address of the MCH drive. It is adjustable from 0-254
and has a factory default value of 128.
60 SERIAL TIMEOUT This parameter makes the serial watchdog timeout period selectable. It has a
minimum value of 10 seconds and maximum value of 65535 seconds. The default is
30 seconds. If no action is to be taken when a serial watchdog timeout occurs, Drive
Parameter #57 (Serial) should be set to W/O TIMER. This will disable the watchdog
timer. Otherwise Drive Parameter #57 (Serial) should be set to WITH TIMER.
If the LAN has started the drive or has modified the Speed Source Selection (MV1),
the Keypad Speed Command (AV1) or the Keypad Setpoint Command (AV2) and a
serial watchdog timeout occurs, the drive is taken out of serial control.
If Drive Parameter #30 (Control) is set to SERIAL AUTO and the drive was running
when the timeout occurred, the drive will also stop the motor by tripping into a
SERIAL FAULT. A fault reset command, issued via Clear Fault (BV1), a keypad stop
or a terminal stop is required to clear the fault.
If Drive Parameter #30 (Control) is set to SERIAL SPEED, then the action to be taken
when a timeout occurs is determined by Drive Parameter #56 (Serial Loss).
When Drive Parameter #30 (Control) is set to SERIAL SPEED the speed reference
being used MUST be set to the drive keypad (-KEY, -MKB, -AKB) or the LAN (-SER)
for the serial watchdog to be active. When Drive Parameter #30 is set to SERIAL
AUTO the serial watchdog will be active with any speed reference.
Also, if the LAN has written to the keypad speed command, the speed source
changes from keypad to serial and the keypad speed command cannot be changed
using the drive keypad. In order for the drive keypad to take control of the keypad
speed command, the drive H/O/A must be toggled to HAND or OFF to release serial
control of the corresponding BACnet® object. The same is true of the keypad
setpoint command and the speed source selection.

RG-MHBAC 8
BACnet Objects
4 MCH BACnet® Objects
The MCH BACnet® Objects are divided into seven types: analog input, analog value, binary input, binary
output, binary value, multi-state input and multi-state value. Sections 4.2 through 4.8 describe each of
these object types and the individual object instances within each.
4.1 BACnet® Object Map
Table 2: BACnet® Object Map for MCH Series Drives
Object
Type 1
Object
Instance
Description (Object Name) Point
Units
Resolution Texts Number
of States
Default
Value
Inactive Active
AI 1 Actual Frequency (OUTPUT FREQ) Hz 0.01 -- -- -- 0
AI 2 Command Frequency (COMMAND FREQ) Hz 0.01 -- -- -- 20.00
AI 3 Load Percent (LOAD PERCENT) % 1.00 -- -- -- 0
AI 4 Total Runtime (RUNTIME HRS) Hr 1.00 -- -- -- 0
AI 5 DC Bus Voltage (DC BUS VOLTS) % 1.00 -- -- -- 0
AI 6 PID Setpoint Command (PID SETPOINT) % 1.00 -- -- -- 50
AI 7 PID Feedback (PID FEEDBACK) % 1.00 -- -- -- 0
AV 1 Keypad Speed Command (KEY SPD CMD) Hz 0.01 -- -- -- 20.00
AV 2 Keypad Setpoint Command (KEY STPT CMD) % 1.00 -- -- -- 50
BI 1 Run/Stop Status (RUN_STOP) -- 1.00 STP RUN -- STP
BI 2 Current Direction (DIRECTION) -- 1.00 FWD REV -- FWD
BI 3 Fault Condition (OK_FAULT) -- 1.00 OK FLT -- OK
BI 4 TB-14 / Relay #2 (TB14_RELAY2) -- 1.00 OFF ON -- OFF
BI 5 TB-15 / Relay #3 (TB15_RELAY3) -- 1.00 OFF ON -- OFF
BI 6 Relay #1 (RELAY1) -- 1.00 OFF ON -- OFF
BO 1 Start/Stop Drive (CMD RUN_STOP) -- 1.00 STP RUN -- STP
BV 1 Clear Present Fault (CLEAR FAULT) -- 1.00 NRM CLR -- NRM
MSI 1 Operational Status (RUN STATUS) -- 1.00 -- -- 16 12
MSI 2 Present Fault (FAULT) -- 1.00 -- -- 25 0
MSI 3 PID Mode (PID MODE) -- 1.00 -- -- 3 0
MSI 4 H/O/A Mode (HOA MODE) -- 1.00 -- -- 3 0
MSI 5 Speed/Setpoint Reference (SPD_STPT REF) -- 1.00 -- -- 19 0
MSV 1 Speed Source Selection (SOURCE SEL) -- 1.00 -- -- 3 0
NOTES:
1. Object Types: AI = Analog Input; AV = Analog Value;
BI = Binary Input; BO = Binary Output; BV = Binary Value;
MSI = Multi-State Input; MSV = Multi-State Value

9 RG-MHBAC
BACnet Objects
4.2 Analog Input (AI) Object Descriptions
Object AI-1: Actual Frequency
This object represents the actual speed of the drive in Hz.
Object AI-2: Command Frequency
This object represents the commanded drive speed in Hz.
Object AI-3: Load Percent
This object represents the drive’s load current as a % of rated current.
Object AI-4: Total Runtime
This object represents the number of hours that the drive has been running since its first
power-up.
Object AI-5: DC Bus Voltage
This object represents the drive's DC Bus Voltage as a percentage of the nominal DC bus
voltage.
Object AI-6: PID Setpoint Command
This object is for monitoring the commanded PID Setpoint. The range of this object is
defined by Drive Parameter #75 (Feedback @ Min) and Drive Parameter #76 (Feedback @
Max).The unit is %.
Object AI-7: PID Feedback
This object is for monitoring the current PID Feedback value at the input specified by Drive
Parameter #74 (PID Feedback). The range of this object is defined by Drive Parameter #75
(Feedback @ Min) and Drive Parameter #76 (Feedback @ Max).The unit is %.
4.3 Analog Value (AV) Object Descriptions
Object AV-1: Keypad Speed Command
This object monitors and controls the Keypad Speed Command (in Hz). The ability to
command this object through the LAN is dictated by the setting of Drive Parameter #30
(Control) and the drive’s current H/O/A Mode (Refer to Object MSI-4).
Object AV-2: Keypad Setpoint Command
This object monitors and controls the Keypad Setpoint Command. The unit for this object
is percent (%). The minimum and maximum values for this object are defined by Drive
Parameter #75 (Feedback @ Min) and #76 (Feedback @ Max), respectively. The range of
adjustment for Drive Parameters #75 and 76 is –32768 to 32767.
The ability to command this object through the LAN is dictated by Drive Parameter #30
(Control) and the drive HOA (Refer to Object MSI-4).

RG-MHBAC 10
BACnet Objects
4.4 Binary Input (BI) Object Descriptions
Object BI-1: Run / Stop Status
This object indicates whether or not the drive is currently running.
Object BI-2: Current Direction
This object indicates the direction in which the drive is currently running.
Object BI-3: Fault Condition
This object indicates whether or not the drive is currently tripped on a fault. This object
returns 0 (OK) if the drive is not in a fault condition or 1 (FAULT) if it currently is faulted.
Object BI-4: TB-14 / Relay #2
This object monitors the state of the drive’s TB-14 or Relay #2 output. This object can be
used to indicate various drive conditions as specified by Drive Parameter #52 (TB14_Relay
#2). Refer to the MCH Installation and Operation Manual (MH01) for more information.
Object BI-5: TB-15 / Relay #3
This object monitors the state of the drive’s TB-15 or Relay #3 output. This object can be
used to indicate various drive conditions as specified by Drive Parameter #53 (TB15_Relay
#3). Refer to the MCH Installation and Operation Manual (MH01) for more information.
Object BI-6: Relay #1
This object monitors the state of the drive’s Relay #1 output. This object can be used to
indicate various drive conditions as specified by Drive Parameter #54 (RELAY1). Refer to
the MCH Installation and Operation Manual (MH01) for more information.
4.5 Binary Output (BO) Object Descriptions
Object BO-1: Start/Stop Drive
This object is used to issue RUN/STOP commands to the drive. The RUN/STOP commands
are placed in the priority array which is then processed to determine the appropriate course
of action. This object reflects the highest priority RUN/STOP command in the priority array.
Therefore, if this object is used to issue a RUN command to the drive but a higher priority
STOP command had been issued by another device, this object will continue to read STP.
NOTE: When in Programming Mode, the drive will not accept START commands from the LAN.
4.6 Binary Value (BV) Object Descriptions
Object BV-1: Clear Present Fault
This object is used to clear the current fault through the LAN. Set this object to CLEAR
(1) to clear the present fault. Once this object has been used to clear a fault, it must be
commanded to NORMAL (0) before it can be used to clear another fault. Consecutive
CLEAR commands cannot be accepted.

11 RG-MHBAC
BACnet Objects
4.7 Multi-State Input (MSI) Object Descriptions
Object MSI-1: Operational Status
This object is for monitoring the actual operating condition of the drive. The value returned
is a number between 1 and 16 which corresponds to one of the following operating states:
Value Name Operational State
1 LOCK Fault Lockout
2 FAULT Fault
3 PEND Start Pending
4 STOP Stop
5 BRAKE DC Brake
6 RUN@0 Run At 0Hz
7 RUN Run
8 ACCEL Accelerating
9 DECEL Decelerating
10 LIMIT Current Limit
11 F DEC Decel Override
12 INVAL Invalid State
13 KSTOP Keypad Stop
14 KSTOP Alternate Keypad Stop
15 RSTOP Remote (Terminal Strip) Stop
16 SSTOP Serial Stop
Object MSI-2: Present Fault
This object indicates the type of fault on which the drive is currently tripped. This object
returns a value between 1 and 25 which corresponds to one of the following fault conditions:
Value Name Fault Value Name Fault
1 NO FAULT No Fault 14 CONTROL Control Fault
2 OUTPUT Output Fault 15 LANGUAGE Language
3 E-STOP E-Stop 16 EXTERNAL External Fault
4 HI VOLTS High DC Bus Volts 17 INTERNAL16 Internal Fault 16
5 HI TEMP High Drive Temp 18 PWR TRAN Power Transient
6 OVERLOAD Thermal Overload 19 INTERNAL18 Internal Fault 18
7 OUTPUT Output Fault 20 INTERNAL19 Internal Fault 19
8 LO VOLTS Low DC Bus Volts 21 INTERNAL20 Internal Fault 20
9 START ER Start Error 22 INTERNAL21 Internal Fault 21
10 BRAKE ER DC Brake Error 23 INTERNAL22 Internal Fault 22
11 FOLLOWER Follower Loss 24 INTERNAL23 Internal Fault 23
12 DB ERROR DB Error 25 SERIAL Serial Comm Loss
13 PWR SAG Power Sag

RG-MHBAC 12
BACnet Objects
Object MSI-3: PID Mode
This object is for monitoring the general state of the drive’s PID mode as specified by Drive
Parameter #70 (PID Mode).
State Name PID Control
1 OFF PID disabled.
2 NORMAL Enable direct-acting system (INC FDBK, DEC MTR SPD)
3 REVERSE Enable reverse-acting system (INC FDBK, INC MTR SPD)
Object MSI-4: H/O/A Mode
This object is for monitoring the drive H/O/A status. If the drive H/O/A is OFF (1) or HAND
(2), serial speed/setpoint and serial start commands will not be accepted from the LAN.
If the drive H/O/A is AUTO (3), depending on the setting of Drive Parameter #30 (Control),
serial speed/setpoint and serial start commands will be accepted. For more information,
refer to Section 3.4.
State Name Accept Serial Command?
Speed/Setpoint Start
1 OFF No No
2 HAND No No
3 AUTO Parameter 30 setting Parameter 30 setting
Object MSI-5: Speed/Setpoint Reference
This object is for monitoring the source of the speed/setpoint reference. States 1 through
9 are speed references. States 10 through 18 are setpoint references. This object must be
in state 1, 9 or 10 for the LAN to be able to command the drive speed. This object must be
in state 11 or 19 for the LAN to be able to command the drive setpoint. The state test table
for this point is as follows:
State Name Description Reference
1 -KEY Keypad Speed Command (Open loop speed control - PID Disabled)
2 -VDC 0-10 VDC on TB-5A (Open loop speed control - PID Disabled)
3 -IDC 4-20 mA on TB-5B (Open loop speed control - PID Disabled)
4 SP#1 Preset Speed #1 (Open loop speed control - PID Disabled)
5 SP#2 Preset Speed #2 (Open loop speed control - PID Disabled)
6 SP#3 Preset Speed #3 (Open loop speed control - PID Disabled)
7 SP#4 Preset Speed #4 (Open loop speed control - PID Disabled
8 -MOP Motor Operated Pot (Open loop speed control - PID Disabled)
9 -SER Serial Speed Command (Open loop speed control - PID Disabled)
10 -MKB Keypad Speed Command (Open loop speed control - PID Enabled)
11 -AKB Keypad Setpoint Command (Closed loop setpoint control - PID Enabled)

13 RG-MHBAC
BACnet Objects
State Name Description Reference
12 -VDC 0-10 VDC on TB-5A (Closed loop setpoint control - PID Enabled)
13 -IDC 4-20 mA on TB-5B (Closed loop setpoint control - PID Enabled)
14 SP#1 Preset Setpoint #1 (Closed loop setpoint control - PID Enabled)
15 SP#2 Preset Setpoint #2 (Closed loop setpoint control - PID Enabled)
16 SP#3 Preset Speed #3 (Open loop speed control - PID Enabled)
17 SP#4 Preset Setpoint #4 (Closed loop setpoint control - PID Enabled)
18 -MOP Motor Operated Pot (Closed loop setpoint control - PID Enabled)
19 -SER Serial Setpoint Command (Closed loop setpoint control - PID Enabled)
4.8 Multi-State Value (MSV) Object Descriptions
Object MSV-1: Speed Source Selection
This object mimics the functionality of the SPEED SOURCE key on the drive keypad. It
is used to determine whether the drive will get its speed/setpoint reference from Drive
Parameter #24 (Auto Source) or Drive Parameter #29 (Hand Source).
State Name Reference Source
1 NORMAL Normal Source
2 HAND Hand Source Only
3 AUTO Auto Source Only
This object allows the user to toggle between OPEN loop speed control and CLOSED loop
PID control when PID mode is ENABLED (refer to MSI-3). The ability to command this
object through the LAN is dictated by Drive Parameter #30 (Control) and the drive HOA
(refer to MSI-4)
For more information on SPEED SOURCE, refer to the MCH Installation and Operation Manual (MH01).
4.9 Reference and Links
MCH Series Variable Frequency Drives visit:
http://www.lenze-actech.com
BACnet and ASHRAE, Inc. visit:
http://www.bacnet.org

AC Technology Corporation
630 Douglas Street • Uxbridge MA 01569 • USA
Sales: 800-217-9100 •Service: 508-278-9100
www.lenze-actech.com
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