WTI CLM-D20 User manual

WTI Part No.: 13667
Rev.: A
CLM-D20
Current Load Monitor
User's Guide

Warnings and Cautions:
Installation Instructions
Secure Racking
If Secure Racked units are installed in a closed or multi-unit rack assembly, they may
require further evaluation by Certification Agencies. The following items must be
considered.
1. The ambient within the rack may be greater than room ambient. Installation should be
such that the amount of air flow required for safe operation is not compromised. The
maximum temperature for the equipment in this environment is 45°C. Consideration
should be given to the maximum rated ambient.
2. Installation should be such that a hazardous stability condition is not achieved due to
uneven loading.
Input Supply
Check nameplate ratings to assure there is no overloading of supply circuits that could
have an effect on overcurrent protection and supply wiring.
Grounding
Reliable earthing of this equipment must be maintained. Particular attention should
be given to supply connections when connecting to power strips, rather than direct
connections to the branch circuit.
No Serviceable Parts Inside; Authorized Service Personnel Only
Do not attempt to repair or service this device yourself. Internal components must be
serviced by authorized personnel only.
• Shock Hazard - Do Not Enter
Disconnect Power
If any of the following events are noted, immediately disconnect the unit from the outlet
and contact qualified service personnel:
1. If the power cord becomes frayed or damaged.
2. If liquid has been spilled into the device or if the device has been exposed to rain or
water.
Two Power Supply Cables
Note that this unit includes two separate power buses, with a power supply cable for each
bus. Before attempting to service or remove this unit, please make certain that both power
cables are disconnected.
Display Power Switch
The back panel of this unit includes a power switch that is used to switch the front panel
LED displays On and Off. Note that this power switch only applies to the front panel
LED displays and does not control power to the outlets on the back of the unit nor shut off
power to the unit.

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1. Introduction
The CLM Current Load Monitor allows you to quickly measure current load
conditions for electronic equipment in a rack mount environment. Total
amperage, wattage and voltage are clearly displayed on two large LED screens,
allowing you to easily determine when circuits are overloaded or unbalanced.
The CLM features two separate power buses; each bus includes its own power
supply connection and two 20 Amp branch circuits with outlets. When the
current load exceeds 80% of the rated value, the CLM can activate an audible
alarm buzzer.
2. Hardware Installation
Connect your AC powered devices to the CLM-D20, and then connect the CLM
to an appropriate power supply as described below:
1. Connect the power cables from your AC powered devices to the power
outlets on the CLM back panel, and then install the supplied cable keepers.
a) First, make certain that both CLM power supply cables are
disconnected from your power supply. Next, loosen (but do not
remove) the two Phillips head screws located on each side of each
power inlet.
b) Slip the Cable Keepers over each supply cable, so the notch on the top
of each keeper secures each cable, and the two slots on the bottom of
each keeper slide over the loosened screws.
c) Tighten the Phillips head screws to attach each cable keeper to the unit,
making certain the cables are securely held in place.
2. Attach the power supply cables to the power inlet connectors on the CLM
back panel, and then snap the power inlet cable keepers into place to secure
the power cables to the CLM.
3. Refer to the safety precautions listed at the beginning of this User's Guide,
and then connect the unit to an appropriate power source. Note that the
CLM-D20 is designed for 100 to 240 VAC, 50/60 Hz operation, and that
each power circuit will support 20 Amps.

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CLM-D20 - Current Load Monitor; User's Guide
3. Unit Description
3.1. Front Panel
The front panel includes Indicators, control buttons and LEDs which are used to
control the measurement of current, watts and voltage as follows:
 Bus A LED Display: A four digit LED display, which indicates current
load, wattage or voltage (depending on which is selected) for Bus A.
 Bus B LED Display: A four digit LED display, which indicates current
load, wattage and voltage (depending on which is selected) for Bus B.
When the "Total A + B" button is pressed, this Display can also show
combined current and wattage for both buses.
 Current Selector Button and Indicators: A Current selector button and
three LED Indicators which are used to display the current load in Amps for
both buses. Each time the "Current" button is pressed, the display function
will change as follows:
• Total: When the "Total" Indicator is lit, the Bus A Display and Bus B
Display will show the total load for the corresponding Bus.
• Ckt 1: When the "Circuit 1" Indicator is lit, the Bus A Display and Bus B
Display will show the show the current load on the Circuit 1 outlet for
each corresponding Bus.
• Ckt 2: When the "Circuit 2" Indicator is lit, the Bus A Display and Bus B
Display will show the show the current load on the Circuit 2 outlet for
each corresponding Bus
www.wti.com
CLM-D20
Current Load Monitor
TOTAL
CKT 1
CKT 2
CURRENT
TOTAL
CKT 1
CKT 2
WATTS
CURRENT
WATTS
QUIET
TOTAL
A + B
VOLTS
VOLTS
BUS A BUS B PRESS FOR 2 SECONDS
TO CHANGE QUIET MODE
8.8.8.8. 8.8.8.8.
12
3456
Figure 1: Front Panel Components

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CLM-D20 - Current Load Monitor; User's Guide
 Watts Selector Button and Indicators: Each time the "Watts" button is
pressed, the display function will change as follows:
• Total: When the "Total" Indicator is lit, the Bus A Display and Bus B
Display will show the total wattage for the corresponding Bus.
• Ckt 1: When the "Circuit 1" Indicator is lit, the Bus A Display and Bus B
Display will show the show the wattage on the Circuit 1 outlet for each
corresponding Bus.
• Ckt 2: When the "Circuit 2" Indicator is lit, the Bus A Display and Bus B
Display will show the show the wattage on the Circuit 2 outlet for each
corresponding Bus
 Volts Selector and Indicator: When the "Volts" button is pressed, the Volts
Indicator will light, and the Bus A Display and Bus B Display will show the
voltage for each corresponding Bus.
 Total A + B Selector Button and Indicators: A selector button and
Indicators which allow you to display the total current or wattage for both
buses combined, and also allows you to activate/deactivate the "Quiet"
Mode. When the "Total A + B" button is pressed, the display function will
change as follows:
• Current: When the "Current" Indicator is lit, the Bus B Display will
show the total current in amps for Bus A and Bus B combined.
• Watts: When the "Watts" Indicator is lit, the Bus B Display will show
the total wattage for Bus A and Bus B combined.
• Quiet: When the "Quiet" Indicator is lit, the CLM's audible alarm buzzer
will be suppressed. To activate or deactivate the Quiet Mode, press and
hold the "Total A + B" button for approximately two seconds. For more
information on the Quiet Mode, please refer to Section 4.1.
Note: When the "Total A + B" button is pressed to show combined
current or wattage values, the total values will be displayed on the Bus B
LED Display, and the Bus A Display will be switched Off.

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CLM-D20 - Current Load Monitor; User's Guide
3.2. Back Panel
The back panel includes Power In connectors for both busses, circuit breakers for
each circuit and four IEC320-C19 Power Outlet connectors.
 Display Power Switch: Controls power to the LED Displays and
Indicators only.
CAUTION: This switch does not control power to the outlets or to the
unit's control components. In order to shut off all power to the unit, you
must unplug the power input cables.
 Bus B Power Connector: An IEC320-C20 power inlet, for connection
to your Bus B Power Supply, as described in Section 2. The CLM-D20 is
designed for 100 to 240 VAC, 50/60 Hz operation, and will support up to 20
Amps per circuit.
 Bus B Circuit Breaker: A 20 Amp Circuit Breaker for Circuit B.
 Bus B Power Outlets: Two IEC320-C19 connectors for Branch Circuit B1
and B2.
 Bus A Circuit Breaker: A 20 Amp Circuit Breaker for Circuit A.
 Bus A Power Outlets: Two IEC320-C19 connectors for Branch Circuit A1
and A2.
 Bus A Power Connector: Same as Item 2 above, except supplies power for
Bus A.
B2 1 2 1 A
CIRCUIT CIRCUIT
12
3
4
5
67
Figure 2: Back Panel Components

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CLM-D20 - Current Load Monitor; User's Guide
4. Operation
The CLM's current measuring functions are controlled by the manual buttons
located on the face panel. Each button is used to select a specific current/
wattage/voltage measurement function, and only one function can be selected at
a given time.
1. Measuring Current:
• Total Current per Bus: To measure the total current for each bus, press
the Current Button to light the "Total" indicator.
• Circuit Current: To measure the current for each branch circuit on each
bus, press the Current Button to light the "CKT 1" or "CKT 2" Indicator.
• Total Current for Unit: To measure the total current for both buses
combined, press the "Total A + B" Button to light the "Current" Indicator.
2. Measuring Watts:
• Total Watts per Bus: To measure total watts for each bus, press the
Watts Button to light the "Total" indicator.
• Circuit Wattage: To measure the wattage for each branch circuit on each
bus, press the Watts Button to light the "CKT 1" or "CKT 2" Indicator.
• Total Watts for Unit: To measure the total wattage for both buses
combined, press the "Total A + B" Button to light the "Watts" Indicator.
3. Measuring Voltage: To measure the total voltage for each Bus, press the
Volts button to light the "Volts" Indicator.

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CLM-D20 - Current Load Monitor; User's Guide
4.1. The Audible Alarm and the Quiet Mode
When the CLM detects that the current consumption for an individual branch
circuit or bus has exceeded 80% of it's rated value, it will sound an audible alarm
buzzer and continually flash the corresponding current LED for the overloaded
bus or branch circuit On and Off.
Once the Audible Alarm has been triggered, it can be deactivated by pressing and
holding the "Total A + B" Button for two seconds.
If necessary, the Quiet Mode can be used to suppress the Audible Alarm entirely.
To enable the Quiet Mode, press and hold the "Total A + B" Button for two
seconds to light the Quiet Mode Indicator. To reactivate the Quiet Mode, press
and hold the "Total A + B" button for two seconds again.

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CLM-D20 - Current Load Monitor; User's Guide
5. Specifications
Front Panel:
LED Display: Two, 4-digit displays, .5 Inch, Blue
Push Buttons: Current, Watts, Volts, Total A + B
LED Indicators: Circuit 1, Circuit 2, Total, Volts, Current, Watts, Quiet
Power:
Current Accuracy: +/-5% @ 25C
Voltage Accuracy: +/-2% @ 25C
AC Inputs: Two IEC320-C20 Connectors
Voltage: 100 - 240 VAC, 50/60 Hz
AC Outputs:
Bus A - Two IEC320-C19 Connectors
Bus B - Two IEC320-C19 Connectors
Circuit Breakers: Two 20-Amp Supplementary Branch Circuit Breakers
Ckt.1, Ckt.2.
Physical / Environmental:
Size:
Height: 1.75" (4.5 cm) - One Rack U
Depth: 8.0" (20.3 cm)
Width: 17.0" (43.2 cm) - 19" Rack Brackets Included
Shipping Weight: Eight Pounds
Operating Temperature: 32F to 122F (0 - 50C)
Humidity: 10 to 90% RH
Agency Approvals: UL, cUL

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CLM-D20 - Current Load Monitor; User's Guide