Dickson PW4 & PW8 Pressure Chart Recorders

Record pressure changes on paper with Dickson PW4 and PW8 pressure chart recorders. Choose a compact 4-inch recorder or a larger 8-inch chart format to suit your installation and recording requirements.

Pressure ranges: Models covering 0–100, 0–200, 0–300, 0–500 or 0–1000 psi, depending on the series.
Recording periods: 24-hour or 7-day operation, depending on the model.
Local recording: Battery-powered chart drive with a visible paper trace.
Selection: Match the pressure range, recording period, connection and chart reference before ordering.

Description
Attachments

See how pressure changes during a test, operating shift or monitoring period with Dickson PW4 and PW8 pressure chart recorders. The circular chart provides a physical record that can be dated, annotated and retained with maintenance or test documentation.

Start with the required pressure range and recording duration, then choose the chart size. The PW4 offers a compact 4-inch format, while the PW8 provides a larger 8-inch chart for reviewing the pressure trace.

Choose a 4-inch or 8-inch pressure recorder

Selection point	PW4 series	PW8 series
Chart diameter	4 inches, approximately 101 mm	8 inches, approximately 203 mm
Model ranges	0–100, 0–200, 0–300 and 0–500 psi	0–100, 0–200, 0–300 and 0–1000 psi
Selection advantage	Compact chart format for installations with limited space.	Larger chart format for easier visual review and annotation.
Recording period	24-hour or 7-day operation according to model and instrument version.	Select the model for the required 24-hour or 7-day period.

Pressure recorder models and matching charts

The table below combines model selection with replacement chart references. Pressure ranges are fixed by the selected instrument; fitting a chart with a different scale does not change the recorder’s measuring range.

Chart size	Model	Pressure range	Recording period	24-hour chart	7-day chart
4 inch	PW470	0–100 psi	24 hours / 7 days	C010	C012
4 inch	PW474	0–200 psi	24 hours / 7 days	C026	C040
4 inch	PW476	0–300 psi	24 hours / 7 days	C022	C036
4 inch	PW479	0–500 psi	24 hours; confirm 7-day capability on the supplied instrument	C028	C056 — only where 7-day operation is supported
8 inch	PW860	0–100 psi	7 days	—	C412
8 inch	PW861	0–100 psi	24 hours	C410	—
8 inch	PW864	0–200 psi	7 days	—	C436
8 inch	PW865	0–200 psi	24 hours	C456	—
8 inch	PW866	0–300 psi	7 days	—	C431
8 inch	PW867	0–300 psi	24 hours	C422	—
8 inch	PW875	0–1000 psi	24 hours	C441	—

Chart packs: The chart references above are listed in packs of 60. Charts are ordered separately from the recorder.

PW479 compatibility note: Earlier product literature specifies 24-hour recording, while Dickson’s 2026 chart matrix lists both C028 and C056. Confirm the instrument’s actual speed capability before ordering 7-day charts.

Pressure connection and operating features

Feature	Details
Pressure accuracy	±2% of full scale
Pressure connection	1/4-inch male NPT fitting
Power	One replaceable AA battery
Typical battery life	Approximately one year
Enclosure protection	NEMA 4X / IP66, subject to correct closure and seal condition
Mounting	Stem or wall mounting, as specified for the selected model
Recording supplies	Matching circular chart paper and replacement recorder pen

Understand full-scale accuracy: On a 0–100 psi recorder, ±2% of full scale corresponds to ±2 psi. On a 0–1000 psi recorder, it corresponds to ±20 psi. Choose the range according to both the maximum pressure and the detail needed in the record.

Accessories and replacement supplies

Reference	Item	Enquiry details
Chart codes listed above	Replacement circular charts	Specify the recorder model, pressure range, recording period and pack quantity.
Recorder pen	Replacement ink pen	Provide the model and existing pen reference or photograph so the correct fitting can be confirmed.
A791	Pressure fitting accessory kit	Confirm the required connection arrangement.
A792	Steam pressure pigtail	Provide the process temperature and pressure for suitability review.
A793	Fire hydrant adapter kit	Confirm the hydrant connection before ordering.
R022	Pressure filter kit with snubber	Confirm compatibility with the selected recorder and process conditions.

Select for the actual pressure measurement

Provide the process medium, normal pressure, maximum pressure and any expected surges. Water, air, oil and steam applications require different checks for wetted-material compatibility, temperature and connection accessories.

For a pressure test, specify the test duration and smallest pressure change that must be identified. A larger chart or longer recording period does not automatically improve the instrument’s pressure accuracy.

When replacing an existing PW4 or PW8, include a nameplate photograph and the code printed on the chart. This helps match the measuring range, chart drive and consumables.

For other chart sizes or combined recording requirements, view the Palmer Wahl 8-inch and 12-inch pressure and temperature chart recorders.

Request pricing and model selection

Contact us for pricing and availability. Please include:

Preferred model or required pressure range.
4-inch or 8-inch chart preference.
24-hour or 7-day recording requirement.
Process medium, temperature and maximum pressure.
Connection details and required installation accessories.
Recorder quantity, chart packs and replacement pen requirements.
Calibration points and certificate requirements, if applicable.

Download

Dickson Recorders Catalogue - (1.96M)