Split Compartment Testing - TCS 700-30 Installation, Operation & Maintenance Manual

Split Compartment Test
Purpose: A product depletion test verifies the proper operation of the air elimination system when the
storage tank for the product being measured is pumped dry. This test is necessary for meters that may
drain a tank completely, such as a vehicle tank meter.
Multiple-Compartment Test Procedure:
1) Begin the test from a compartment (ideally the largest compartment) containing an amount of fuel
equal to or less than one-half the nominal capacity of the prover being used. Operate the meter at the
normal full flow rate until the compartment is empty. There are several methods for determining that
the compartment is empty. There may be a significant change in the sound of the pump. There may
be visual evidence that the compartment has run dry. The meter register may stop entirely or may
begin to count erratically (pause, resume running, then pause, then run again.)
2) Continue the test until the meter indication stops entirely for at least 10 seconds. If this occurs,
proceed to Step 3. If the meter indication fails to stop entirely for a period of 10 seconds, continue to
operate the system in this condition for 3 minutes.
3) Close the valve from the empty compartment, and if top filling, close the nozzle or valve at the
end of the delivery hose. Open the valve from another compartment containing the same product.
Carefully open the valve at the end of the delivery hose. Pockets of vapor or air may cause product
to splash out of the prover. The test results may not be valid if product is splashed out of the prover.
Appropriate attire and protection is required, and always use caution.
4) Continue delivering product at the normal full flow rate until the liquid level in the prover reaches the
nominal capacity.
5) Close the delivery nozzle or valve and stop the meter. Allow any entrained air to settle, then read the
prover sight gauge.
6) Compare the meter indication with the actual delivered volume in the prover.
7) Calculate the meter error. Apply the Product Depletion Test Tolerance to determine whether the
meter error is within acceptable limits. Refer to NIST Handbook 44 for further information.
Product Depletion Test Tolerance for Vehicle-Tank Meters:
Marked Maximum Flow Rate
Less than 100 GPM (380 LPM)
100 GPM (380 LPM) or greater
The results of the product depletion test may fall outside of the applicable test tolerance as this is a
stand-alone test.
The test draft should be equal to at least the amount delivered by the device in 1 minute at its
maximum discharge rate, and in no case should it be less than 50 gallons.
Page 16
Product Depletion Test Tolerance
Check us out at www.TCSmeters.com!
0.5%
0.6%
TCS900003, Rev.6
04/26/2016