Mission Communications PN OP750 User manual

Expansion
Modules
PMS 660
Installation Manual
PN OP750 Safe Module Plus
PN OP464-30/31 Pulse Input (2 channels each, 4 total)
PN OP653 Digital Input (8 channel, isolated)
PN OP465 Analog Input (4-channel)
PN OP461 Analog Output (2-channel)
New!

2
Welcome,
Thank you for choosing Mission Communications for your monitoring and alarm
needs. Mission is committed to providing the highest quality of SCADA solutions.
All products go through a strict testing regimen before leaving the facility to
ensure a seamless installation experience.
Mission provides customers with 24-hour access to Technical Support.
Additionally, Mission hosts a wide range of information that can be remotely
accessed through the web portal, such as training videos, support documents,
and more. The Mission goal is to provide customers with the latest technology
and designs while ensuring great value.
Weekly training webinars are available most Wednesdays at 2 P.M. Eastern.
Quarterly newsletters and training videos on are available on the website. Visit
123mc.com to sign up for the webinar and to nd training videos and the
newsletter archive. Mission Technical Support is available at [phone]
option 2 for further assistance.
Thank you,
The Mission Team
Warning: This symbol indicates there is caution or warning to avoid damage to your property or
product.
Warning: Follow requirements for eld wiring installation and grounding as described in NEC and your
local/state electrical codes.
Note: This symbol indicates that there is something that requires your special attention.
This device complies with part 15 of the FFC Rules. Operation is subject to the following two conditions: (1) This
device may not cause harmful interference, and (2) this device must accept any interference received, including
interference that may cause undesired operation.
Mission offers a variety of related documents. Scan the QR code
with a smartphone or visit 123mc.com/literature to view.

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Contents
Chapter 1: Overview
Chapter 2: Location
Chapter 3: Communications Cable
Chapter 4: Single Expansion Module Hookup
Chapter 5: Pre-Installation
Chapter 6: Safe Module Plus (PN OP750)
Chapter 6.1: SMP Pulse Inputs
Chapter 7: Pulse Input (PN OP464)
Chapter 8: Digital Input (PN OP653)
Chapter 9: Analog Input (PN OP465)
Chapter 10: Analog Output (PN OP461)
Appendix A: Upgrades from Legacy RTUs, Wet Well Modules,
and Pulse Counter Option Boards
Appendix B: Troubleshooting
Appendix C: Multiple Module Hookup
Appendix D: Long Cable Runs, Terminating Resistor
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6
6
7
8
9
14
15
17
18
19
20
21
22
23

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Chapter 1: Overview
Expansion modules increase the monitoring possibilities of the MyDro remote
terminal unit (RTU). Mission provides options for expanded input/output (I/O)
based on ADVANTECH modules. The new Safe Module Plus expansion module
brings useful features to sewer lift station monitoring, fresh water pump lock-
out applications, and rain sensing applications. Read more about this in the
specication sheet. Additional modules are available in Pulse Input, Digital Input,
Analog Input, and Analog Output.
The MyDro RTU will recognize the module once it is installed and will publish
the readings to the LCD screen and the web portal. Congurable options will be
presented on the LCD screen under the Cong. menu. The web portal is used
to create alarm notication rules for the new I/O including alarm delays, analog
threshold, and ow (pulse) thresholds. The MyDro 850 RTU is recommended
for use with Digital Input, Analog Input, and Analog Output Expansion Modules.
Either the MyDro 150 or 850 is appropriate for use with the Safe Module Plus.
The expansion modules provide signal conditioning, isolation, ranging, and
A/D and D/A conversion. Digital communication to the MyDro is based on a
unique device ID and cable (RS485 2-wire, plus power). The device ID has been
set by Mission at the factory as indicated on the label.
Multiple expansion modules can be daisy-chained together (wired in parallel). At this
time the MyDro supports one each of the Safe Module Plus, Digital Input, Analog
Input, and Analog Output Expansion Modules. It supports two Pulse Input Expansion
Modules. See Table 1 for more details.
Setup forms for all modules are available online. Use the camera of a smartphone
to email the form. Please complete and send the form to Technical Support as
quickly as possible so reports will be labeled appropriately and the notication
system will enunciate call-outs properly.

5
Table 1:
Expansion module part numbers, functions, and power requirements.
Max power* requirement of the Module does not include instrumentation.
MyDro
Expansion
Modules
On Main
Board
Expansion
Available I/O
Dev ID
in
Decimal
Max
Power* RTU ADVANTECH PN
Safe Module
Plus
OP750 DI 4 on
mainboard
not used
1 intrinsically
safe oat input
(presented
as DI 4) and
locally available
as a relay
output, 4 pulse
channels
TBD 0.5 W M150 or
M850 N/A
Digital
Input
OP653
8 DI 9–DI 16 10 1 W M850 4051-BE
Analog Input
OP485 2 AI 3–AI 6 20 1.2 W M850 ADAM-4017+-CE
Analog
Output
OP461
0 AO 1–AO 2 40 3 W M850 4024-B1E
Pulse
Input
OP464-30
0 1–2 30 2 W M150 or
M850 4080-DE
Pulse
Input
OP464-31
0 3–4 31 2 W M150 or
M850 4080-DE
Note: Labels are attached to indicate Mission I/O nomenclature. For
example, Mission expanded digital I/O starts with digital input (DI) 9 to
complement the way expanded digital inputs appear on the web portal
ADVANTECH documentation describes that input as DI 0. Mission does not
currently support all features and inputs of some expansion modules.

6
Chapter 2: Location
In most cases, the included 8-foot communications cable allows the expansion
module(s) to be mounted on the back panel of the control cabinet and the other
end connected to the nearby MyDro RTU.
The expansion module(s) can be mounted on a DIN rail or directly to a backplate
in the control cabinet. Signal cables should be run in conduit if the module is
mounted in the Mission NEMA 1 or NEMA 4 enclosures. No load carrying wires
should be run in the same conduit as signal wires.
The RS485 communications standard (differential balanced line over twisted pair)
supports distances up to 4,000 feet.
Chapter 3: Communications Cable
The RJ45 end of the included cable plugs into the RS485 port (left side) of
the MyDro. One twisted pair is for communications while the other powers the
expansion module(s). Do not connect or remove the RJ45 end into the MyDro
board until all wiring to the expansion module is complete. The four conductors
terminate on the expansion modules as follows (see Table 2):
Table 2:
RS485 Connection
Module Pin # Label Wire Color
10 GND Bk—Black
9 +Vs R—Red
8DATA - Gr—Green
7DATA + W—White

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Wiring Best Practices:
• Do not run signal wires parallel to load wires. If they must cross, do so at a
right angle.
• Extend the RS485 cable, rather than the cables running to the instruments, if
the remote sensors are a distance away.
Chapter 4: Single Expansion Module Hookup
Avoid routing the communications cable parallel to other load carrying conductors.
Figures 1A and 1B demonstrate a single module network powered by the
communications cable. For an example of a multiple module hookup, see Appendix
C.
Warning: Wiring the expansion modules with the RJ45 communications
cable connected to the MyDro can potentially cause damage to the circuit
board.
Figure 1B:
Other Expansion Modules
Figure 1A:
Safe Module Plus

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Chapter 5: Pre-Installation
Note: Electronic keys are supplied with each RTU. They can be congured
at the web portal for a variety of functions (track site visits, acknowledge
alarms, service mode, cong. mode). For pre-installation, keys should have
service and cong mode privileges.
1. Conrm the MyDro rmware is appropriate (see Table 3). If an update
is required, contact Mission Technical Support to initiate an over-the-
air update.
2. If the RTU is active and enabled for alarm notications use the
electronic key to place the MyDro RTU into service mode so alarm
notications will be suppressed during the installation.
3. Disconnect AC power from control panel.
4. Verify that no power is present in the work area by using a volt meter.
5. Mount the module with the self-tapping screws provided.
Table 3:
Minimum rmware versions required to support each expansion module.
Expansion Module MyDro Firmware Required
Safe Module Plus ≥ 16.3
Pulse Input ≥ TBD
Digital Input ≥ TBD
Analog Input ≥ TBD
Analog Output ≥ TBD

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Note: The relay can drive a load up to 10 amps at 120 VAC
Safe Module Plus Overview
The Safe Module Plus (SMP) is an exclusive device
that speeds and simplies the installation of a Mission
MyDro 150 or 850 RTU. It supports four pulse counting
channels that can be used with rain tipping buckets
or pulse-based ow meters. It provides an intrinsically
safe circuit to a oat so that the state of the oat can be
transmitted by the MyDro RTU for alarm notications
as well as to energize a built-in-relay that is typically
associated with a local buzzer or light for sewer lift
station applications, or service-pump lock-out for clear
well applications.
Note: For legacy (M110, M800) RTU upgrades
that utilize the Wet Well Module, see Appendix A.
NEC Rule 22-704
National Electric Code (NEC)
Rule 22-704 offers comprehensive
criteria for classication of
hazardous locations. Sewer lift
stations are generally considered
Class I, Division I environments
and require corresponding
intrinsically safe apparatus.
Methane (explosive) and
hydrogen sulde (corrosive) are
common vapors present in these
environments.
The oat circuit associated with
the SMP is certied as intrinsically
safe: Class I, Div I, II, III, Groups
D–G.
Chapter 6: Safe Module Plus (PN OP750)
See the specication sheet for
overview and application data
and the UL Control Document
for intrinsically safe application
and installation information.
UL Control Document for
OP-750 Safe Module Plus
SAFETY DESCRIPTION:
The Safety Module Plus apparatus is to be installed in an
Unclassied Location while providing intrinsically safe output for
Class I, Division 1, Groups A, B, C and D Hazardous Locations in
the US and Canada. Additionally for [AEx ia Ga] X in the US and
[Ex ia Ga] IIC X in Canada. The apparatus is intended for use in
ambient temperature range of -20C to 60C.
WARNINGS
OP-750 series must be installed, operated and maintained only
by qualied personnel, in accordance to the relevant national/
international installation standards (e.g. ANSI/ISA RP12.06.01
Installation of Intrinsically Safe System for Hazardous (Classied)
Locations, National Electrical Code NEC ANSI/NFPA 70 Section
504 and 505, Canadian Electrical Code CEC) following the
established installation rules, particular care shall be given to
segregation and clear identication of I.S. conductors from non
I.S. ones.
De-energize power source (turn off power supply voltage) before
plugging or unplugging the terminal block (J4) when oat is
installed in Hazardous Locations or unless area is known to be
nonhazardous.
Warning: Explosion Hazard: to prevent
ignition of ammable or combustible
atmospheres, disconnect power before
servicing or unless area is known to be
nonhazardous.
Danger d’Explosion: pour prévenir une
inammation de l’atmosphère inammable
ou combustible, couper l’alimentation
avant de réparer à moins de savoir que
l’emplacement n’est pas dangereux.
Units must be protected against dirt, dust, extreme mechanical
(e.g. vibration, impact and shock) and thermal stress, and casual
contacts.
If enclosure needs to be cleaned use only a cloth lightly
moistened by a mixture of detergent in water.
Electrostatic Hazard: to avoid electrostatic
hazard, the enclosure must be cleaned only
with a damp or antistatic cloth.
Danger électrostatique: pour éviter le
danger électrostatique, l’enveloppe doit être
nettoyée au moyen d’un chiffon humide ou
antistatique. Any penetration of cleaning
liquid must be avoided to prevent damage
to the unit.
Failure to properly install or use the equipment may risk damage
to the unit or severe personal injury. The unit cannot be repaired
by the end user and must be returned to the manufacturer or his
authorized representative. Any unauthorized modication must be
avoided.
Warning: substitution of components may
impair Intrinsic Safety.
Avertissement: le remplacement des
composants peut dégrader la Sécurité
Intrinsèque.
It is tested for a maximum for AC power supply (Um) of 120 VAC.
Control equipment must not use or generate more than 120 V rms
or dc with respect to earth.
Selected intrinsically safe equipment must be third party listed
as intrinsically safe for the application, and have intrinsically safe
entity parameters conforming with Table 1 (see next page).
SPECIAL CONDITIONS FOR SAFE USE
The device does not meet the 500V rms dielectric requirement
between the IS circuit and earth.
ASSOCIATEDAPPARATUS
In sewer lift station applications, the high level oat (located in the
sump) including the cable is in a hazardous location. This simple
apparatus as dened and installed in accordance with Article
504.2 and with Article 504.10(D) of the National Electrical Code
(ANSI/NFPA 70), or other local codes, must comply with the entity
parameters described in Table 1 (see next page).
Capacitance and inductance of the eld wiring from the
associated apparatus to the Safe Module Plus shall be calculated
and must be included in the system calculations as shown
in Table 1. Cable capacitance, Ccable, plus intrinsically safe
equipment (oat switch) capacitance, Ci must be less than the
marked capacitance. Likewise, cable inductance plus intrinsically
safe equipment (oat switch) inductance (Li) must be less than the
marked inductance.
Where the cable capacitance and inductance per foot are not
known, the following values shall be used: Ccable = 60 pF/ft. (200
pF/m), Lcable = 0.2 μH/ft (1.0 μH/m.) These calculated maximum
lengths do not allow for any switch capacitance or inductance.
(The cable length must be less than 800 feet not including
allowances for the switch.)
For installations in which both the Ci and Li of the intrinsically
safe apparatus exceeds 1% of the Ca (or Co) and La (or Lo)
parameters of the associated apparatus (excluding the cable),
then 50% of Ca (or Co) and La (or Lo) parameters are applicable
and shall not be exceeded. The reduced capacitance shall not be
greater than 1 μF for Groups C and/or D (IIB and/or IIA), and 600
nF for Groups A and B (IIC).
The values of Ca (or Co) and La (or Lo) determined by this
method shall not be exceeded by the sum of all of Ci plus cable
capacitances and the sum of all of the Li plus cable inductances in
the circuit respectively.
This associated apparatus has not been evaluated for use in
combination with another associated apparatus.
Where multiple circuits extend from the same piece of associated
MyDro Expansion
Safe Module Plus
Intrinsically safe circuit to oat, speeds
installation, and supports pulse inputs
For Hazardous Environments
Most sewer lift stations are considered hazardous locations per the
National Electric Code (NEC Rule 22-704). The MyDro Safe Module
Plus allows the state of a high-level oat (located in the hazardous
location) to be shared with both the local control panel and the Mission
remote terminal unit (RTU) while complying with NEC requirements for
hazardous environments. The oat-sensing circuit is certied for Class I,
Division I (methane) environments typical of sewer lift stations.
Speeds Installation
The optional module connects to the MyDro 150 or 850 RTU with a
quick-connect communications cable. The cable powers the module and
includes the RS485 communications link between the two components.
The RS485 standard is capable of reliable communications up to 4,000
feet, allowing the module to be located closer to the sensed elements.
The enclosure is compatible with standard DIN rail. Terminals are front-
facing.
High Wet WellAlarms Even When AC Has Failed
High wet well events are reported even when there is no AC power to the
station because of the backup battery associated with MyDro unit.
Relay—Local Alarm
A built-in relay can drive a local alarm light and buzzer based on oat.
Relay—Lock-Out Functions
The relay can be used in specialty applications where safety lock-out
functions are desired. Aselectable debounce (time delay) can be set
for the included relay to avoid short cycling of equipment because of a
bouncing oat. For example, in clean water applications the relay can be
included in the control circuit of a service pump and used to lock-out the
pump before the supply runs dry, as indicated by a normally open (N/O)
low-level oat. The Mission notication system can be set to dispatch a
notication, such as “service pump lock-out activated because low supply
level.”
Four Pulse Channels
The module supports four pulse channels. They are typically used with
rain tipping buckets and pulse-based ow meters. The inputs support
dry, open collector, and wetted circuits. Non-volatile memory maintains
the pulse count for extended power outages or if communication cable is
disconnected. Pulse counts accumulate even if the MyDro RTU is ofine
as long as it has power.
Supervision
The MyDro will report RS485 communication failure as well as
intrinsically safe circuit failure if those conditions occur.
• Reduceinstallation time and complexity
• Float circuit designed for hazardous locations
typical of a sewer lift station
• Dispatcheshigh wet well alarms even if AC
power fails
• Spawn oat signal for multiple purposes
• Supports4 pulse channels

10
Sewer Lift Station Applications
Figure 2:
Sewer lift station application
Float and Panel Wiring for Sewer Lift Station Applications
The two-wire connection to the oat is not polarity sensitive. Locate (or intercept
if a retrot application) the high-level oat wires and terminate them on the SMP
lower oat terminals. Locate or re-terminate the other two wires (that complete
the circuit to the local alarm) between relay common and relay N/O.
The SMP module (located in a non-hazardous location) senses the state of
oat (in the hazardous area) in an intrinsically safe manner. The oat tip is
communicated to the Mission alarm notication system and the local relay is
energized to illuminate the local alarm light.

11
Figure 3:
Service pump lock-out application
Service Pump Lock-Out Applications
The relay can be used for other applications including fresh water applications
requiring a pump lock-out. For example, a service pump drawing from a clear
well, or below ground storage tank may be commanded to run by either local
control or by the Mission Tank and Well Control Package (an automated remote-
control system). A properly located low-level oat (N/O) in the supply tank is
tipped (closed) when the level is adequate (higher than the suction of the pump),
therefore the pump control circuit is enabled. If or when the oat drops, the relay
opens, thereby locking out the local pump from operating dry.
Float and Local Wiring for Service Pump Applications
The low-level oat is wired to the lower SMP terminals labeled oat. The SMP
relay terminals labeled common are wired in series with the other components
involved in controlling the coil of the motor starter (HOA switch, over temp, over
pressure, other safety switches).

12
Debounce
Turbulent waters near the tipping point of a oat can result in rapid contact
closure cycles. To reduce the side effects of this situation, two types of debounce
are offered. First, the local relay can be set with a debounce by way of the front
facing rotary switches. Secondly, an alarm notication delay can be set from the
web portal (Start Menu > Setup > RTU Setting > RTU Conguration)
Note: Generally sewer lift station applications are best served with no local
relay debounce since the relay is only used to drive a local alarm light or
buzzer. However, an alarm notication delay may be useful.
Note: Pump lock-out applications may benet from a local relay debounce
setting, as short cycling the pump can lead to premature pump failure.
AC Failure and Battery
Since the MyDro supplies the SMP with power and is backed up by battery, the
change in oat status will be reported even after AC failure.
SMP Startup and Test
Verify connections are correct, secure, and labeled. Power up the station. The
RTU display should illuminate and complete the connection sequence. The RTU
must be online for the next steps.
Note: An ofine RTU will allow limited access to conguration menu options
related to getting online. Technical Support is available to assist with
connection issues.
The MyDro display is normally shown with a black background. It will turn yellow
when in service or cong. mode. The duration of the service mode is 60 minutes
by default but can be modied from the web portal (Start Menu > Setup > RTU
Setting > RTU Conguration). If pre-installation steps were followed and the
installation was relatively fast, the RTU should re-synchronize in service and
cong. modes for the remaining time. If not, present the key and wait a few
seconds for the key to be validated.

13
Note: If a relay debounce has been set via the rotary switches, wait the
appropriate time.
1. Conrm with Mission Tech Support that MyDro has been paged to
accept SMP.
2. The green LED on front panel of SMP should illuminate.
3. Tip the oat. Use the touch screen to evaluate the state of DI 4. DI
4 on the MyDro Digital screen should illuminate. The changing input
state should also reect correctly on the web portal.
4. Log into the web portal and proceed to Start Menu > Setup > RTU
Setting > RTU Info to label the digital input and set the normal state
properly. A high-level oat is generally a N/O instrument.
5. If the output relay has been utilized then verify that the device
(example: local alarm light) is working.
6. Exercise each pulse counter channel to assure proper operation. The
pulse count will reect on the third window behind the Status button
on the MyDro display. The value should reect on the web portal
within two minutes for MyDro 850 and 15 minutes for MyDro 150
RTUs.
7. Perform a fail-safe test by disconnecting the Mission communication
cable from the MyDro (the RS485 terminal). Tip the oat. The local
alarm (buzzer or siren) associated with the local control panel should
operate as normal since interposing relay on the SMP does not need
to be powered for current to ow through that relay’s normally closed
contacts. If notications are enabled from your web portal, a wire
fault alarm should be dispatched to your our your staff because of
the disconnected communications cable. This completes the fail-safe
tests.
8. Reconnect the communications cable to the MyDro to resume normal
operations.

14
Figure 4B:
Active pulse input
Figure 4A:
Dry contact pulse input
Chapter 6.1: SMP Pulse Inputs
The SMP supports four pulse inputs. They are generally used with rain tipping
buckets and pulse ow meters.
Changes to pulse readings are reported every 15 minutes for the MyDro 150 and
every two minutes for the MyDro 850.
The minimum pulse width is 16 milliseconds (8 milliseconds high and 8
milliseconds low). Input impedance is 50 megohms.
Figure 4C:
24V DC example - Active pulse input with
optional voltage divider
Figure 4D:
Open collector NPN transistor
Pulse
P1+
GND
1 2 3 4 5
Pulse
P1+
GND
1 2 3 4 5
Pulse
P1+
GND
1 2 3 4 5
Pulse
P1+
GND
1 2 3 4 5
Open collector with NPN transistorActive pulse input with voltage divider
Active pulse inputDry contact pulse input
+
_
4K 1K
Active Source
0–24 VDC
+
_
Active Source
0–5 VDC
Pulse
P1+
GND
1 2 3 4 5
Pulse
P1+
GND
1 2 3 4 5
Pulse
P1+
GND
1 2 3 4 5
Pulse
P1+
GND
1 2 3 4 5
Open collector with NPN transistor24V DC example
Active pulse input with voltage divider
Active pulse inputDry contact pulse input
+
_
4K 1K
Active Source
0–24 VDC
+
_
Active Source
0–24 VDC
Pulse
P1+
GND
1 2 3 4 5
Pulse
P1+
GND
1 2 3 4 5
Pulse
P1+
GND
1 2 3 4 5
Pulse
P1+
GND
1 2 3 4 5
Open collector with NPN transistorActive pulse input with voltage divider
Active pulse inputDry contact pulse input
+
_
4K 1K
Active Source
0–24 VDC
+
_
Active Source
0–5 VDC
Pulse
P1+
GND
1 2 3 4 5
Pulse
P1+
GND
1 2 3 4 5
Pulse
P1+
GND
1 2 3 4 5
Pulse
P1+
GND
1 2 3 4 5
Open collector with NPN transistorActive pulse input with voltage divider
Active pulse inputDry contact pulse input
+
_
4K 1K
Active Source
0–24 VDC
+
_
Active Source
0–5 VDC

15
Chapter 6.2: SMP DIN Rail Mount and Release
The SMP can be mounted on a DIN rail, placing the SMP onto the DIN rail and
rotating down will engage the lower latch that will lock the SMP onto the DIN Rail.
To remove the SMP from the DIN rail, insert a at head screw driver into the open
slot on the metal latch on the bottom back side of the enclosure, pull the latch
down using the leverage of the screwdriver and rotate the enclosure upward and
pull off the rail.

16
Chapter 7: Pulse Input Expansion Module
(PN OP464)
The MyDro supports two Pulse Input Expansion Modules for a total of four
channels. It is generally used with rain tipping buckets and pulse ow meters.
Note: If used, the second Pulse Input Expansion Module must be ordered
as PN OP464-31 so the device address is set to 31.
Changes to pulse readings are reported every 15 minutes for the MyDro 150 and
every two minutes for the MyDro 850.
The minimum pulse width is set by rmware to be 16 milliseconds (8 milliseconds
high and 8 milliseconds low). Input impedance is 50 megohms. The module
consumes 2 watts.
Dry Inputs
Dry inputs (no voltage), typical of a rain tipping bucket, for channel 1 connect to
terminal IN 1 and terminal D.GND. Likewise, channel 2 inputs connect to terminal
IN 2 and terminal D.GND (see Figure 5A).
Figure 5A:
Dry contact input (rain tipping bucket) for channel 1

17
Active Pulse
Some ow meters source the voltage (active pulse). The Pulse Input Expansion
Module supports up to 5 VDC wetted circuits (see Figure 5B). Polarity must be
observed.
Figure 5B:
Active pulse wiring: Logic level 0: 0–0.8 V. Logic level 1:+2.4 V to 5 V
D.GND is common to (Blk) GND terminal
Flow meters that source voltages greater than 5 volts can be accommodated with
a voltage divider circuit consisting of properly sized resistors (see Figure 5C).
Figure 5C:
Active pulse wiring with voltage divider circuit (1K/(1K+4K)= 20%.
24 V source is reduced to 4.8 V.

18
Chapter 8: Digital Input Expansion Module
(PN OP653)
Eight digital inputs can be added to the MyDro (for a total of 16) with the Digital
Input Expansion Module (see Figure 6). These inputs are logically treated as
alarm inputs, meaning that changes in state are reported in real-time. They
cannot be congured as pump start/runtime accumulators.
End-of-line resistors (wire supervision) are not supported by the Digital Input
Expansion Module.
The status of expanded inputs (9–16) can be read from LEDs on the expansion
module as well as the MyDro LCD screen.
Figure 6:
Dry Contact Wiring Diagram
Logic level 1: close to GND, Logic level 0: open

19
Chapter 9: Analog Input Expansion Module
(PN OP465)
The Analog Input Expansion Module adds four analog inputs to the two that are
on the mainboard.
Analog values are reported every two minutes with the MyDro 850. Analog
expansion is not supported with the MyDro 150.
The module supports 4–20 mA current inputs or 0–5 volt inputs (see Table 4 and
Figure 7). Selection between these inputs requires the conguration of a jumper
inside the expansion module as well as a software switch selection on the MyDro
conguration screen.
Table 4:
Jumper settings for 4–20 mA or 0–5 V
Figure 7:
4–20 mA current loop on Channel 3, where + is the signal from the transducer

20
Chapter 10: Analog Output Expansion Module
(PN OP461)
The Analog Output Expansion Module adds two current loop, 4–20 mA output
channels (see Figure 8).
The output impedance of the Analog Output Expansion Module is 0.5 ohms. The
maximum current load resistance is 500 ohms.
Figure 8:
Analog output current loop on output channel 2