Overview
Calculation
Precautions
Examples
Overview
Teradek products may be used with a variety of external power options, including accessory power cables, battery adapter plates, and replacement batteries with DC barrel or P-Tap connections that allow simultaneously powering a Teradek product with another device from the same battery.
These power options are listed on the Teradek online store within each respective product category.
To calculate the approximate run-time when using external battery power sources you need the following items:
- the Teradek product's power draw in Watts
- the battery's rated capacity in Amp Hours
- the battery's rated Voltage
- optionally, if the battery's Watt Hour rating is provided by the manufacturer then this value may be used instead of items (2) and (3)
Item 1 is found on Teradek's website from the product specs, while items 2, 3, and/or 4 are determined from the battery manufacturer's specifications.
Calculation
To calculate the approximate battery runtime:
- convert the capacity from Milliamp Hours to Amp Hours by dividing by 1000; if the battery capacity is already given in Watt Hours then skip directly to step 3 below
- multiply Amp Hours by the Voltage of the battery to get Watt Hours
- finally, divide the battery's capacity in Watt Hours by Cube's Watt average rating to get estimated runtime in hours
- since the battery will not completely discharge, you should estimate 80-90% of this value as the approximate battery runtime depending on how conservative you want your calculation to be, the life of the battery cells, etc.
Precautions
1. Powering Teradek products which contain internal batteries from smaller capacity external batteries
Teradek products with an internal battery (e.g. Cube x55, Bolt Pro TX, Bond Pro, VidiU, etc.) can draw a higher Watt rating if the internal battery is low and the product is charging from its external power input.
This higher Watt rating is listed on the Teradek product specification page.
When the Teradek product is charging its internal battery and pulling power at this higher level, it can drain smaller batteries such as the Canon LP-E6 more rapidly than the batteries may have been designed to handle.
Therefore, when using smaller capacities batteries like the LP-E6, be sure to monitor the Teradek product and swap out batteries when it has drained the external battery so that:
- minimal time is spent by the Teradek product running off its internal battery, and subsequently
- minimal time is spent charging the internal battery after the swap so that the Teradek product returns to using its typical / lower power draw
2. External batteries used to power multiple devices simultaneously
When a single battery is used to simultaneously power multiple devices (e.g. Anton Bauer or V-Mount style battery powering a camera and Teradek product), you need to consider all possible devices drawing from that battery when estimating battery run-time.
- ensure that the possible power draw from all devices doesn't overrun the battery's maximum sustained output power (listed in Watts)
- ensure that the possible current draw from all devices doesn't overrun the battery's maximum sustained output current (listed in Amps)
Examples
Examples of different Teradek products and battery combinations are provided below for reference.
To determine approximate runtime with a different battery, simply substitute the appropriate values into the formula.
Bolt Pro TX / RX
This example will estimate runtime with a Canon LP-E6 battery.
- The Bolt Pro TX has an average power draw of 4.5 Watts (10 Watts if charging the internal battery, see the precautions above)
- The Bolt Pro RX has an average power draw of 6 Watts
- The Canon LP-E6 battery has a rated Voltage of 7.2V, and a rated capacity of 1800 mAh
Bolt Pro TX
- convert the LP-E6 capacity from Milliamp Hours to Amp Hours by dividing by 1000 : (1800 mAh / 1000 milliamps per Amp ) = 1.8 Amp Hours
- multiply Amp Hours by the Voltage of the battery to get Watt Hours : 1.8 Amp Hours * 7.2 Volts = 12.96 Watt Hours
- divide the battery's capacity in Watt Hours by the Bolt TX's Watt average rating to get estimated runtime in hours:
(12.96 Watt Hours / 4.5 Watts) ~= 2.88 hours - estimate that 80% of the battery will discharge, and rounding for significant figures: 2.88 hours * 0.8 ~= 2.3 hours or 138 minutes
Bolt Pro RX
- convert the LP-E6 capacity from Milliamp Hours to Amp Hours by dividing by 1000 : (1800 mAh / 1000 milliamps per Amp ) = 1.8 Amp Hours
- multiply Amp Hours by the Voltage of the battery to get Watt Hours : 1.8 Amp Hours * 7.2 Volts = 12.96 Watt Hours
- divide the battery's capacity in Watt Hours by the Bolt RX's Watt average rating to get estimated runtime in hours:
(12.96 Watt Hours / 6 Watts) ~= 2.16 hours or 130 minutes - estimate that 80% of the battery will discharge, and rounding for significant figures: 2.16 hours * 0.8 ~= 1.7 hours or 102 minutes
Bond II
This example will estimate runtime with a Sony BP-U60 equivalent battery manufactured by SWIT (sold by Teradek as the BIT-649).
- The Bond II has an average power draw of 3 Watts for the unit itself, and up to 2.5 Watts for each USB modem connected to a USB port. Since there are 6 USB ports, there can be a total of 3 Watts + (6 * 2.5 Watts) = 18 Watts
- The SWIT battery has a rated Voltage of 14.4V, and a rated capacity of 4400 mAh
- convert the SWIT battery capacity from Milliamp Hours to Amp Hours by dividing by 1000 : (4400 mAh / 1000 milliamps per Amp ) = 4.4 Amp Hours
- multiply Amp Hours by the Voltage of the battery to get Watt Hours : 4.4 Amp Hours * 14.4 Volts = 63.36 Watt Hours
- divide the battery's capacity in Watt Hours by the Bond II's maximum possible Watt rating to get estimated runtime in hours:
(63.36 Watt Hours / 18 Watts) ~= 3.52 hours - estimate that 80% of the battery will discharge, and rounding for significant figures: 3.52 hours * 0.8 ~= 2.8 hours or 168 minutes
Cube
This example will estimate runtime with a Sony NP-F970 equivalent battery manufactured by SWIT (sold by Teradek as the BIT-647).
- The Cube has an average power draw of 3 Watts for the unit itself (10 Watts if charging the internal battery, see the precautions above)
- NOTE: if using a USB modem or other device connected directly to the Cube's USB port, up to 2.5 Watts may be additionally drawn by the USB device. This additional amount must be added to the base power draw of the Cube, so you may estimate up to 6 Watts total.
- The SWIT battery has a rated Voltage of 7.2V, and a capacity rating of 47 Watt Hours provided by the manufacturer
- divide the battery's capacity in Watt Hours by the Cube's average Watt rating to get estimated runtime in hours:
(47 Watt Hours / 3 Watts) ~= 15.67 hours - estimate that 80% of the battery will discharge, and rounding for significant figures: 15.67 hours * 0.8 ~= 12.5 hours or 750 minutes
VidiU
This example will estimate runtime with a Canon BP-970 equivalent battery manufactured by SWIT (sold by Teradek as the NIBL-641).
- The VidiU has an average power draw of 3 Watts for the unit itself (10 Watts if charging the internal battery, see the precautions above)
- NOTE: if using a USB modem or other device connected directly to the VidiU's USB port, up to 2.5 Watts may be additionally drawn by the USB device. This additional amount must be added to the base power draw of the VidiU, so you may estimate up to 6 Watts total.
- The SWIT battery has a rated Voltage of 7.2V, and a capacity rating of 47 Watt Hours provided by the manufacturer
- divide the battery's capacity in Watt Hours by the VidiU's average Watt rating to get estimated runtime in hours:
(47 Watt Hours / 3 Watts) ~= 15.67 hours - estimate that 80% of the battery will discharge, and rounding for significant figures: 15.67 hours * 0.8 ~= 12.5 hours or 750 minutes
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