Next, look to see if you have access to the HVAC equipment schedule to determine what kind of units will be installed. Some of the different types may be as follows: 01. Split Systems, which would have an air handler and a condensing unit 02. Package units, which connect in one location 03. Gas Packs, which usually take less ampacity 04. Electric units, which would take more ampacity 05. Heat Pumps, which would take the most ampacity 06. Boilers 07. Chillers 08. VAV Valves 09. Air Handlers 10. TWU 11. Ductless Split units 33 Check for the fan schedule also. This will tell voltage and phase, along with any special wiring needed. Most of this information should be located on the electrical drawings. Look for a Disconnect Schedule like the example below: A disconnect schedule makes it easy. As shown in the example above, all the information that you need for the estimate, except for the distance, is located in one place. I like to place the distance in the “Notes” space, which keeps everything in one place. If the engineer does not provide a disconnect schedule, you should create one on your own. . 34 For each run, you need to create an assembly for Sealtight/LiquidTite. You assembly could resemble the example below: 01. 6’ of Liquid-tight—Size as needed 02. 2-Liquid-tight Connectors—Size as needed 03. 16’ of grounding conductor—Size as needed 04. 16’ x number of current caring conductors.—Size as needed 05. 1-Strap—Size as needed 06. 5-Screws The Disconnect Schedule above shows (3) circuits that fit this assembly of products and they are CU-1, CU-2, and CU-4 You would just multiply the QTY above by (3) for quick results. You could end up with something like the following example: 35 No matter the size of the project, if you breakdown the plans in small sizes, it is easy to handle. The next step in the HVAC takeoff would be the feeder portion of the circuit. We will use the same method for the feeder as we did for the Disconnect and liquidtite. Below is a list of items needed for the ¾ runs: After we add the distance of raceways together, it will just be a matter of multiplying this list x the number of runs, which we have identified as being (3). As shown in the sample Disconnect Schedule above the distance has been added to the schedule. This length should include any additional raceway that is needed for the up the and down portion of the feed. The next step is to add the 3 lengths of raceway and enter that length in the assembly. Then multiply the material x (3). The results could look like the following example: This is an easy concept to grasp and it works for all phases of estimating. The heading of the above material could be labeled: To CU-1-CU-2-CU-3 for identification. 36 One Line Diagram Above is an example of a simple one line diagram. No matter how large or small, you approach it in the same manner. First, list the gear by name. 01. MD panel 02. Panel A 03. Panel B 04. Panel K 05. 3-Pole Lighting Contactor. Mech held 06. Time clock. Tork #EW201 Note: We suggest including the disconnects that are not listed on the one line in your Request for Gear Quote. Provide a panel Schedule and specification sheets when submitting the gear for quotation. The supply house should follow the specifications and items listed for quotation. You need to make notes of the following: 01. Voltage 02. Phase 37 03. Nema configuration 04. AIC rating 05. Main Breaker of Main Lug 06. Top fed or bottom fed. 07. Surface or flush mounted 08. Special size restrictions 09. Any special gear notes such as: A. TVSS B. Switching breakers C. Labeling D. Special metering E. Digital read outs F. Remote monitoring G. ISO Ground H. SE Rated I. Construction J. Copper or Aluminum bus. K. Etc. Send the Gear quote and Lighting Quote out as soon as possible to ensure proper bidding time. Mounting the gear Take notice to see if special attention is given to the installation of the panels. Note: Check to see if seismic engineering is required. This can be quite expensive. Let’s start by looking at the panel schedule of the MDP. 38 We note the following: 01. 120/240/3PH/4W (So this project will be unique since it has a delta service) Hot or wild leg 02. 600 amp 03. Main Breaker 04. N3R ( So it will be mounted outside) 05. Surface Mounted 06. SE Rated 07. 30K AIC 08. I Line construction 09. The specifications call for a copper buss. 10. No special mounting needs We will add the mounting products of the panels to the estimate. MDP Mounting hardware 01. 6-1/2” lead anchors ( for brick) 02. 6-1/2 Bolts 03. 6-1/2 Fender washers Panel A and B Mounting Hardware 04. 8-3/8” Lag screws 05. 8-3/8” Fender washers Panel K mounting hardware 06. 4-1/2” lag screws 07. 4-1/2” Fender washers Same way for the time clock and the lighting contactor. Most estimators will just say mounting hardware. Miscellaneous allowance of $ ___. We now have the Gear “Request for Quotation” sent out and the panels mounted in place. Installing the raceways to power the gear is next.
/wp-content/uploads/2020/02/electrical-estimating-software.webp 0 0 admin /wp-content/uploads/2020/02/electrical-estimating-software.webp admin2019-03-20 04:53:412019-03-20 04:53:41Free Estimating Help #18