Digital Loggers

PoE Injector FAQs

Updated 09/07/2017. Download a 24V or -48V User's Guide
Just $295!  Call now (408) 330-5599.

Frequently Asked Questions


What are the DC power, current and voltage ratings?
What's new in the product?
How much voltage loss can I expect in an Ethernet cable?
How can I connect external batteries?
What will / won't the product do?
Are you building a Gig-E variant?
Does it support reverse polarity?
Why is the loud alarm sounding?
How can I destroy the product?
How do I set up network access from Windows?
How do I set up network access from an Apple Macintosh? - Thanks to John McClintock
How do I set up Internet access from a home router? -Thanks to Mike G.
What is the current firmware version?
How do I enable AutoPing?
How do I use Wake on Lan?
What's the PoE pinout?
What's the ground stud for?
How do I jumper the battery charger?
What components do I need to build a remote DC powered site?
What is the 24V model "cut out" voltage?
How can I tell if a PoE cable is shorted or a device is wired in reverse polarity?
What's the Scripting Language all about?
What's syslog?  How can I keep an event log?
What is the default IP address
How do I reset to defaults
What is the default password?
On initial setup, I can't establish a Ethernet communications from a Windows PC.  Help! Do I need a crossover cable?
How can I control the switch from my own applications?  
How can I send HTTP requests?
Can you develop custom firmware for my application?
Can you develop custom hardware for my application?
What are the AC current and voltage ratings?
What is the power consumption?
Do you support PowerMan?
Can you explain the auto-ping settings?
What are the CRITICAL and PROTECT functions?
Do you have a Visual Basic.NET example program?  Thanks to Alan Holmes
Do you have a Python programming example?
Do you have a C++ programming example?
Do you have a .NET programming example?
Do you have a Java programming example?
Do you have a compiled Windows command line tool or a Perl example?
Do you have a Crestron control module?
Where can I find iPhone, iPad, or Android apps?


Question: What are the current and voltage ratings?
Answer:
  15V Model 24V Model -48V Model
AC Input Voltage 90-130 or 180-240 (please specify when ordering)
Max Input Power 188W 194W 190W
Max Total Output 150W 156W 150W
Max Current Per Port 2A 1.5A 800mA
Float Charge Voltage 13.9V 27.8V 52V
Avg Charge Current 1A .5A 350mA
Vdrop (battery to POE) 500mV Regulated 375mV
SIDAC voltage 20V 40V 90V
 

Question: How do I connect the charging jumper?
Answer: A battery trickle charger is included in the injector.  It is connected by default at the factory using a bridging clip on the back of the injector.
Since we've already set it up, and since it won't interfere with an external charger, no changes should be needed.. 

For POSITIVE GROUND systems (ie -48V)

The CHG terminal connects to the NEG battery terminal.  The POS battery terminal is bonded to ground internally.


For NEGATIVE GROUND systems (ie 15V or 24V PoE, ie UBNT Passive 24V)

The CHG terminal connects to the NEG battery terminal.  The POS battery terminal is bonded to ground internally.


Question: What's the ground stud for?
Answer: This is an important connection point. It protects both your attached equipment and the injector itself from ESD and surges.  Connect it to the best local ground point, ie. electrical panel, telecom ground bus, ground rod, tower frame, etc. 



High currents may pass through this point, so heavier ie, 10AWG cable or thicker is appropriate.  Leaving this unconnected will give you only the chassis ground and the 3-wire AC plug ground, which are high impedance paths.  Put simply, if you don't connect the ground lug, you won't have full ESD protection. Leaving this off may also induce noise on your Ethernet cable.  Do it right...


Question: How much voltage loss can I expect in Ethernet cable?
Answer: Here's a handy online calculator.

Question: Why is the loud alarm sounding?
Answer: A potentially dangerous over-current condition has been detected. Disconnect the cable immediately. Check and correct wiring. Common causes include:
  • Ground faults (ie. wrong polarity connection to ground at the powered device (PD).
  • Short circuits in cable or connections.
  • PD polarity and/or voltage doesn't match injector.

If you detect any heating in any Ethernet cable, disconnect it.  That's a potential hazard.


Question: What's new in the product?
Answer: In 2017 we completed field test of a 48V high power gigabit version, which will ship around 10/1/17

 

In May, 2016 we redesigned the 24V regulator board to include a separate isolated  regulator for every port.  The regulation is now completely independent on each device.  This makes it virtually impossible for noise, surges, or overloads on one port to affect the other ports.

 

In 2015, we reached the 10,000 unit milestone and made a number of firmware improvements.  We are now working on gigabit versions for AirFiber and similar applications Thanks for your support!.

 

In 2014, we revised the PCB and surge suppression to handle high current ESD.  We also selected a new fan vendor for longer-life and quieter operation.

 

In 2013, we added:

  1. Remote voltage monitoring for battery voltage (charge condition)
  2. Remote PoE output voltage monitoring
  3. PoE over-current detect is now visible from voltage monitor (in addition to audio alarm)
  4. AC line voltage fail detect
  5. Surge suppression improvements.  Please connect the chassis ground to take advantage of them :)

 

The product was launched in 2012, and we received a lot of great feedback from WISPs.  In 2012 we added:

  1. Additional voltage regulation in the 24V models (to prevent POE over-voltage if an external charger is connected).
  2. Thermal protection.  Automatically resets when things cool down.
  3. Audio alert if a short-circuited cable or PoE device is detected.
  4. Additional surge protection in all models.
  5. Quad fans for redundancy. We use ball-bearing fans, but all mechanical parts can break.  Don't worry, even one fan will do it.
  6. We've stretched the rack mount ear slots (if your rack doesn't quite conform to specs, it will still fit.)

 

Firmware improvements are ongoing.  Find a full list here.


Question:  How can I destroy the product? 
Answer:   There are fifty ways to leave your lover, and at least 8 ways to destroy this product (or try...)

  1. Dunk it in water.  This is an indoor product, exposure to weather will kill it.  No warranty on that.  Please no warranty claims for old "Tough Cable".
  2. Lightning strikes.  We have at least 10 different surge protection circuits inside.  Even with all that, a near or direct lightning strike will kill it... out of warranty.
  3. Connect the battery backwards.  Won't hurt it at all.  We thought of that.
  4. Overheat it.  Nope. Thought of that too.  Unit will automatically reset itself when things cool down.
  5. Over-voltage on the battery input. Typically, you'll just  blow the fuse. Replace it with 8A fast-blow on the 24V units, 4A on the -48.  You'll be up and running.  Need fuses?  Email us, we'll send them gratis.
  6. Short circuits on the output terminals.  Just sounds an audio alarm. Remove the RJ-45 cable, fix the wiring, and plug it back in.  In about a minute, the unit will reset the port and you'll be fine after that.
  7. Connect a 120V unit to 240V mains.  You'll  blow a safety fuse on the internal power supply, and need to send in for service.  If you need 220-240V, just specify when ordering and we'll be glad to configure it that way.  Sorry, due to the extra surge suppression required, AC input voltage is not auto-sensing.
  8. Millions of power cycles.  It's possible to damage both the injector and the attached devices by using a DC charge controller without UVLO.  This can cause the power to cycle continuously and eventually damage things.  In a DC powered site, chose a controller with both OVP and UVLO.

Question:    Are you building a giabit PoE variant?
Answer:      Yes, weshould have them finished by October 2017. Let us know what features you want.  Email engineering@digital-loggers.com  Your vote counts.


Question:    What components do I need to build a remotely powered DC site using the PoE injector?
Answer:    In addition to the load (ie. APCam, PtP link, AP, etc), you'll need a battery, some source of power, ie wind or solar, and most importantly a charge controller with OVP and UVLO features. Over Voltage Protection is needed for reasonable battery life. Under Voltage Lockout is needed to correctly reset attached devices as well as the DIN relay and to prevent oscillation when the battery is nearly discharged.  Don't neglect the UVLO feature - using a charge controller without one may corrupt Flash in the PoE injector or cause the attached devices to fail due to thousands of oscillating power cycles.


Question:  What is the 24V injector's cutout voltage / sequence? 
Answer:     The injector will not cut-out if AC power measures 75VAC or higher. When AC fails, the injector is designed not to cut out above 18VDC as measured at the battery.  The 24V PoE output voltage will decline gradually as the battery discharges. Battery condition can be monitored using the metering feature.  Cutout of the internal control relays occurs around 12-14V.  Note that the injector is not designed as a UVLO / UVCO controller, nor is it a charge controller for external chargers.  If you're using an external DC source like solar or wind power, please review the information on the battery page.  Don't neglect the UVLO feature - using a charge controller without one may corrupt Flash in the PoE injector or cause the attached devices to fail due to thousands of oscillating power cycles.


Question:  What is the typical / maximum  power consumption? 
Answer:    

DC Fans Control Board Relays (each)
4.3W 3.1W 310mW
     
AC Input Max Charge Out Max PoE Out
193W 14W 150W Total

Question:  How can I tell if a cable is shorted? 
Answer:    An audio alert will sound when a shorted cable or radio is connected, or if a device attempts to draw more than 1.5A per port.
Solution:   Disconnect the cable immediately and troubleshoot the cabling/device.  Make sure that the PoE polarity matches.  For safety, don't reconnect until the trouble is confirmed and repaired.


Question: What will/won't the product do?
Answer: The injector is not a solar or wind controller. If AC power fails, the injector will immediately switch to battery power and provide POE by drawing power from the battery string.   In the -48V units, output voltage approximately 0.5V lower than the external DC battery input voltage per the 802... standards.  Because of the tight voltage tolerances necessary for certain 24V equipment, the 24V POE injector includes an additional voltage regulator which prevents the POE voltage from exceeding 24.0V.  The injector does not contain a hub, switch or router. RJ-45 POE jacks are simply loop-through. Each port (including the control port) is completely independent from the others. All ports are 10/100, and are not Gig-E compatible.
Question: What is the current version of firmware?
Answer: The current version is  on the update page  Find the revision history here, and firmware update instructions here.

Question: What is the PoE standard pinout?
Answer: The -48 injector uses the 802.3af 10/100 B standard as shown below:
 
802.3af Standards A and B
PINS on Switch T568A Color T568B Color  10/100 DC on Spares (mode B)   10/100 Mixed DC & Data (mode A)   1000 (1 Gigabit) DC & Bi-Data (mode B)   1000 (1 Gigabit) DC & Bi-Data (mode A) 
Pin 1 Pair 3 Tip
white/green stripe
Pair 2 Tip
white/orange stripe
Rx + Rx +             DC + TxRx A + TxRx A +             DC +
Pin 2 Pair 3 Ring
green solid
Pair 2 Ring
orange solid
Rx - Rx -              DC + TxRx A - TxRx A -              DC +
Pin 3 Pair 2 Tip
white/orange stripe
Pair 3 Tip
white/green stripe
Tx + Tx +             DC - TxRx B + TxRx B +             DC -
Pin 4 Pair 1 Ring
blue solid
Pair 1 Ring
blue solid
DC + unused TxRx C +             DC + TxRx C +
Pin 5 Pair 1 Tip
white/blue stripe
Pair 1 Tip
white/blue stripe
DC + unused TxRx C -             DC + TxRx C -
Pin 6 Pair 2 Ring
orange solid
Pair 3 Ring
green solid
Tx - Tx -             DC - TxRx B - TxRx B -             DC -
Pin 7 Pair 4 Tip
white/brown stripe
Pair 4 Tip
white/brown stripe
DC - unused TxRx D +             DC - TxRx D +
Pin 8 Pair 4 Ring
brown solid
Pair 4 Ring
brown solid
DC - unused TxRx D -             DC - TxRx D -

Taken from Wikipedia's PoE page


Question: What is the default IP address?  How do I reset to defaults?  What is the default password?
Answer: If you have lost the IP address or admin password, follow this procedure to reset to the default IP address of 192.168.0.100:
  • Press and hold the reset button for 2 seconds to reset the network settings, user name and passwords.

The default master login is "admin" and default password is "1234".  This procedure resets the admin login and IP addres


Question: How can I use "reverse" polarity Cambian equipment?  Like an ePMP1000 for instance?
Answer: The best way is with an adapter cable.  The cable should be wired to swap the blue pair with the brown pair. You can then add other "standard" polarity equipment to the same PoE injector.

Question: On initial setup, I can't establish a Ethernet communications from a Windows PC.  Help!
Answer: If your default Windows settings won’t access the controller, use a crossover cable and follow these steps to reach the controller’s IP. 
  • Before adding an IP, close network programs and browsers.
  • Go to the Network Settings – Local Area Network or use the keyboard shortcut <Windows-R> - type “ncpa.cpl” and click OK. 
  • Right click on your LAN connection and choose “Properties”
  • Highlight “Internet Protocol” and click the “Properties” button.
  • Make note of the current settings.
  • Select "Use the following IP address".
  • Enter an IP address such as 192.168.0.5.
  • Enter a subnet mask of 255.255.255.0.
  • Delete any gateway entry.
  • Close all windows for the configuration to take effect.
  • Start your Browser and type 192.168.0.100 in the URL field. The index page should be displayed.
  • The default user name is "admin" (lower case) and password is “1234”
  • Set the IP address of the unit to your network, then restore your settings.

Question: Can you explain the auto-ping settings?
Answer:

Enabling auto-ping

To enable auto-ping, the check-box to the left of the IP address must be checked, then the change button pushed. You will get a message "Autoping will automatically be enabled after 10 successful pings". This prevents rebooting units before conditions are properly established.

Time Between Pings

The time between which each ping is set. The time between pings to a particular device is (Time_Between_Pings * Number_of_devices_enabled_in_the_ping_list).

Ping failures before reboot

Number of times the ping has to fail (in a row) on a given device before it is power cycled.

Times to attempt reboot

Number of times to attempt power cycling before giving up and disabling auto-ping.

Device reboot delay

Length of time after a power cycle before checking for a response from the device. This allows a device or computer time to completely boot up.

Question: How can I control the switch from my own applications?
Answer:  Download the latest User Utility. Your application can use HTTP or serial port communications. There are programming examples from several languages listed in the top section. Also included is PowerMan support for Linux.

Windows users can download a Perl interpreter to run the script version.  This script (ver 4.0) is compatible with all DLI power controllers.

Question: Can you develop custom firmware for my application?
Answer: Gladly.  We've done this for many customers.  Our programming rate is $75/hour.  After we agree on a -very specific- project description, we can send you an estimate of the time involved to code, debug and test.   

Question: Can you develop custom hardware for my application?
Answer: Gladly.  We've done this for many customers.   Please call with your requirements

Question: What are the AC current and voltage ratings?
Answer: Voltage input is 90-135VAC, or 200-240VAC (switch selectable).  Maximum input current 2.4A RMS.  Max power-on inrush is 8A.

Question: Do you support PowerMan?
Answer: Yes, absolutely.  The latest code is added to the tarball.  Download the latest User Utility here.


If we haven't answered your questions here, please call (408) 330-5599 or
We'll be glad to help.

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