Table A1.
Components and price list for cave Pearl data logging platform and the surface (drip sensor; Case Study 1) and submersible (tilt flow meter; Case Study 2) environmental housings. The 2018 prices are based on delivery to Midwest USA. Items without a suggested supplier are generally available at electronics retailers or hardware stores.
| Component | Source | Cost/Unit |
|---|---|---|
| Data Logging Platform | ||
| Generic 3.3v 8MHz Pro Mini clone [328P] | eBay | $2.00 |
| DS3231 & AT24C32 I2C RTC Module | eBay | $1.25 |
| CR2032 RTC battery | eBay | $0.50 |
| (2) 12mm M2 nylon standoffs for RTC | various | $0.40 |
| microSD card adapter for Raspberry Pi | eBay | $1.00 |
| 128-256Mb microSD (Nokia, Sandisk) (used) | eBay | $3.00 |
| 3xAA series, or 3 single AA plastic battery holders | eBay | $1.00 |
| Deans T-Style Battery Connector | eBay | $1.00 |
| 4 inch or 2 inch Oatey Test Cap | Menards [#39103/#6893208] | $0.50 |
| (2) WSD1241 Micro 4B Plug | Advantage Hobby | $3.00 |
| Misc parts: wire, caps, resistors, LED, etc | various | $1.50 |
| Total in US Dollars: | $15.15 | |
| Drip Sensor Housing (Case study #1) | ||
| FERNCO QWIK Cap, 4 inch | Menards [#QC-104] | $3.90 |
| 4 inch PVC Drain Cap | Zoro Tools [#G6182477] | $1.25 |
| Charlotte 4-in dia PVC Test Cap | Lowes [#23408] | $2.05 |
| ADXL345 accelerometer module (w 3.3v input) | eBay | $2.00 |
| Total in US Dollars: | $9.20 | |
| Flow Sensor Housing (Case Study #2) | ||
| (2) 2 inch Formufit white table caps | Home depot [#F002ECT-WH-4] | $4.50 |
| (1) Formufit End Cap, 2 inch Slip fit | Home depot [#F002EEC-WH-10] | $1.60 |
| (6 inches) Formufit 2 inch Sch. 40 PVC pipe | Home depot [#P002FGP-WH-5] | $1.50 |
| 2 inch Schedule 40 PVC slip fit coupling | Menards [#K00955T] | $0.50 |
| (2) 1/2 inch NPT Threaded PVC Plug Sch. 80 | Zoro Tools [#G2988937] | $2.80 |
| 332 O-Ring, EPDM, 3/16 dia. | Zoro Tools [G2506561] | $1.00 |
| (3) 3-1/2 inch, 1/4-20, Nylon 6/6 Hex Bolt, Slotted | Amazon | $1.00 |
| OR: Threaded Rod 1/4-20 x 4 ft, Nylon | Zoro Tools [#G0540757] | |
| (3) Black 6/6 Nylon Hex nut, 1/4-20 | Zoro Tools [#G2205567] | $0.25 |
| Epoxy, Loctite Hysol 30-CL, 50mL | Zoro Tools [#G2233901] | $1.50 |
| GY-511 LSM303DLHC Module | eBay | $3.00 |
| Total in US Dollars: | $17.65 | |