# WattNode Pulse – Option Kh – Watt-Hours Per Pulse

## Overview

* Option Kh* (watt-hours per pulse or Kh Watthour Constant) specifies number of watt-hours that must accumulate for each pulse generated by the meter. Each pulse includes an ON (conducting) and OFF period. The number of watt-hours may be small, even less than one, or large; 1000 watt-hours (one kilowatt-hour) is a common choice.

**Note:**The WattNode Pulse – Model Selector can be used to automatically calculate valid Kh Options.

## Specification

To order a WattNode^{®} Pulse meter with * Option Kh*, you must also indicate the current rating of the current transformers (CTs) you are using with the meter. For example, the following sets the current transformer rated amps to 150 and the watt-hours per pulse to 100 Wh (0.1 kWh):

Opt CT=150,Kh=100

You may want to convert between *Kh* “watt-hours per pulse” and *Pk* “pulses per kilowatt-hour”. The following equations show the conversions.

For example, if you want 10 pulses per kilowatt-hour, you would solve for *Kh* as follows:

10 pulses per kilowatt-hour | |

100 watt-hours per pulse |

## Option Hz Equivalence

Specifying * Option CT* and

*is essentially equivalent to specifying a custom full-scale pulse frequency (*

**Option Kh***). It isn’t possible to specify both*

**Option Hz***and*

**Option Hz***at the same time. The following table contains equations to compute the full-scale frequency (Hz) values as a function of the specified CT amps and*

**Option Kh***Kh*(watt-hours per pulse) values.

Model | Full-Scale Hz Equations | |
---|---|---|

Standard Bidirectional Pulse Outputs Option DPO (Dual Positive Outputs) |
Option P3 (Per-Phase Outputs) | |

WNB-3Y-208-P WNB-3D-240-P |
||

WNB-3Y-400-P WNB-3D-400-P |
||

WNB-3Y-480-P WNB-3D-480-P |
||

WNB-3Y-600-P |

**Note:**These equations are complex for. Contact customer support if they are required or use the WattNode Pulse – Model Selector.**Option PV**

The general equation follows.

where,

*NVAC*is the nominal line-to-neutral voltage*CT*is the current transformer rating in amps*PpPO*is phases per pulse output (as explained in the Power and Energy Equations section of the user manual)*Kh*is the watt-hours per pulse